BEATCALC: Beat the Calculator!

From the BEATCALC mailing list:
a weekly service from B. Lee Clay, archived here by the Math Forum.
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Squaring Numbers

1. Squaring a 2-digit number beginning with 1
2. Squaring a 2-digit number beginning with 5
3. Squaring a 2-digit number beginning with 9
4. Squaring a 2-digit number ending in 1
5. Squaring a 2-digit number ending in 2
6. Squaring a 2-digit number ending in 3
7. Squaring a 2-digit number ending in 4
8. Squaring a 2-digit number ending in 5
9. Squaring a 2-digit number ending in 6
10. Squaring a 2-digit number ending in 7
11. Squaring a 2-digit number ending in 8
12. Squaring a 2-digit number ending in 9
13. Squaring numbers made up of ones
14. Squaring numbers made up of threes
15. Squaring numbers made up of sixes
16. Squaring numbers made up of nines
17. Squaring numbers in the twenties
18. Squaring numbers in the thirties
19. Squaring numbers in the forties
20. Squaring numbers in the fifties
21. Squaring numbers in the sixties
22. Squaring numbers in the seventies
23. Squaring numbers in the eighties
24. Squaring numbers in the hundreds
25. Squaring numbers in the two hundreds
26. Squaring numbers in the three hundreds
27. Squaring numbers in the four hundreds
28. Squaring numbers in the five hundreds
29. Squaring numbers in the six hundreds
30. Squaring numbers in the seven hundreds
31. Squaring numbers between 800 and 810
32. Squaring numbers in the nine hundreds
33. Squaring numbers between 1000 and 1100
34. Squaring numbers between 2000 and 2099
35. Squaring numbers between 3000 and 3099
36. Squaring numbers between 4000 and 4099
37. Squaring numbers between 5000 and 5099
38. Squaring numbers between 6000 and 6099
39. Squaring numbers between 7000 and 7099
40. Squaring special numbers (3's and final 1)
41. Squaring special numbers (3's and final 2)
42. Squaring special numbers (3's and final 4)
43. Squaring special numbers (3's and final 5)
44. Squaring special numbers (3's and final 6)
45. Squaring special numbers (3's and final 7)
46. Squaring special numbers (3's and final 8)
47. Squaring special numbers (3's and final 9)
48. Squaring special numbers (6's and final 1)
49. Squaring special numbers (6's and final 2)
50. Squaring special numbers (6's and final 3)
51. Squaring special numbers (6's and final 4)
52. Squaring special numbers (6's and final 5)
53. Squaring special numbers (6's and final 7)
54. Squaring special numbers (6's and final 8)
55. Squaring special numbers (6's and final 9)
56. Squaring special numbers (9's and final 1)
57. Squaring special numbers (9's and final 2)
58. Squaring special numbers (9's and final 3)
59. Squaring special numbers (9's and final 4)
60. Squaring special numbers (9's and final 5)
61. Squaring special numbers (9's and final 6)
62. Squaring special numbers (9's and final 7)
63. Squaring special numbers (9's and final 8)
64. Squaring special numbers (1 and repeating 3's)
65. Squaring special numbers (1 and repeating 6's)
66. Squaring special numbers (1 and repeating 9's)
67. Squaring special numbers (2 and repeating 3's)
68. Squaring special numbers (2 and repeating 6's)
69. Squaring special numbers (2 and repeating 9's)
70. Squaring special numbers (3 and repeating 6's)
71. Squaring special numbers (3 and repeating 9's)
72. Squaring special numbers (4 and repeating 3's)
73. Squaring special numbers (4 and repeating 6's)
74. Squaring special numbers (4 and repeating 9's)
75. Squaring special numbers (5 and repeating 3's)
76. Squaring special numbers (5 and repeating 6's)
77. Squaring special numbers (5 and repeating 9's)
78. Squaring special numbers (6 and repeating 3's)
79. Squaring special numbers (6 and repeating 9's)
80. Squaring special numbers (7 and repeating 3's)
81. Squaring special numbers (7 and repeating 6's)
82. Squaring special numbers (7 and repeating 9's)
83. Squaring special numbers (8 and repeating 3's)
84. Squaring special numbers (8 and repeating 9's)
85. Squaring special numbers (9 and repeating 3's)
86. Squaring special numbers (9 and repeating 6's)
87. Squaring a repeating 6-digit number
88. Squaring 2 rep. numbers, dividing by square of single digit

    Multiplying Numbers

89. Multiplying two selected 2-digit numbers (same 1st digit) [1]
90. Multiplying two selected 2-digit numbers (same 1st digit) [2]
91. Multiplying two selected 2-digit numbers (same 2nd digit)
92. Multiplying two selected 3-digit numbers (middle digit 0)
93. Multiplying two selected 3-digit numbers (middle digit 1)
94. Multiplying two selected 3-digit numbers (middle digit 2)
95. Multiplying two selected 3-digit numbers (middle digit 3)
96. Multiplying two selected 3-digit numbers (middle digit 4)
97. Multiplying two selected 3-digit numbers (middle digit 5)
98. Multiplying two 2-digit numbers with a difference of 1
99. Multiplying two 2-digit numbers with a difference of 2
100. Multiplying two 2-digit numbers with a difference of 3
101. Multiplying two 2-digit numbers with a difference of 4
102. Multiplying two 2-digit numbers with a difference of 6
103. Multiplying two 2-digit numbers with a difference of 8
104. Multiplying two 2-digit numbers with a difference of 10
105. Multiplying a 2-digit number by 1 1/25
106. Multiplying a 2-digit number by 1.1
107. Multiplying a 2-digit number by 1 1/9
108. Multiplying a 2-digit number by 1 1/8
109. Multiplying a 2-digit number by 1 1/7
110. Multiplying a 2-digit number by 1 1/6
111. Multiplying a 2-digit number by 1 1/5
112. Multiplying a 2-digit number by 1 2/9
113. Multiplying a 2-digit number by 1 1/4
114. Multiplying a 2-digit number by 1 2/7
115. Multiplying a 2-digit number by 1.3
116. Multiplying a 2-digit number by 1 1/3
117. Multiplying a 2-digit number by 1 3/8
118. Multiplying a 2-digit number by 1 2/5
119. Multiplying a 2-digit number by 1 3/7
120. Multiplying a 2-digit number by 1 1/2
121. Multiplying a 2-digit number by 1 4/7
122. Multiplying a 2-digit number by 1 3/5
123. Multiplying a 2-digit number by 1.6
124. Multiplying a 2- or 3-digit number by 1 2/3
125. Multiplying a 2-digit number by 1 5/7
126. Multiplying a 2-digit number by 1 3/4
127. Multiplying a 2-digit number by 1 4/5
128. Multiplying a 2-digit number by 1 5/6
129. Multiplying a 2-digit number by 1 6/7
130. Multiplying a 2-digit number by 1.9
131. Multiplying a 2-digit number by 2.1
132. Multiplying a 2-digit number by 2 1/9
133. Multiplying a 2-digit number by 2 1/7
134. Multiplying a 2-digit number by 2 1/5
135. Multiplying a 2-digit number by 2 2/9
136. Multiplying a 2-digit number by 2 1/4
137. Multiplying a 2-digit number by 2.3
138. Multiplying a 2-digit number by 2 1/3
139. Multiplying a 2-digit number by 2 3/8
140. Multiplying a 2-digit number by 2.4
141. Multiplying a 2-digit number by 2 2/5
142. Multiplying a 2-digit number by 2 4/9
143. Multiplying a 2- or 3-digit number by 2 1/2
144. Multiplying a 2-digit number by 2 4/7
145. Multiplying a 2-digit number by 2.6
146. Multiplying a 2-digit number by 2 5/8
147. Multiplying a 2-digit number by 2 2/3
148. Multiplying a 2-digit number by 2.7
149. Multiplying a 2-digit number by 2 5/7
150. Multiplying a 2-digit number by 2 3/4
151. Multiplying a 2-digit number by 2 7/9
152. Multiplying a 2-digit number by 2 6/7
153. Multiplying a 2-digit number by 2.9
154. Multiplying a 2-digit number by 3.1
155. Multiplying a 2-digit number by 3 1/8
156. Multiplying a 2-digit number by 3 1/7
157. Multiplying a 2-digit number by 3 1/6
158. Multiplying a 2-digit number by 3.2
159. Multiplying a 2-digit number by 3 2/9
160. Multiplying a 2-digit number by 3 1/3
161. Multiplying a 2-digit number by 3.4
162. Multiplying a 2-digit number by 3 3/7
163. Multiplying a 2-digit number by 3 4/9
164. Multiplying a 2-digit number by 3 1/2
165. Multiplying a 2-digit number by 3.6
166. Multiplying a 2-digit number by 3 4/7
167. Multiplying a 2-digit number by 3 5/8
168. Multiplying a 2-digit number by 3 2/3
169. Multiplying a 2-digit number by 3.7
170. Multiplying a 2-digit number by 3 5/7
171. Multiplying a 2-digit number by 3 3/4
172. Multiplying a 2-digit number by 3 4/5
173. Multiplying a 2-digit number by 3 6/7
174. Multiplying a 2-digit number by 3 7/8
175. Multiplying a 2-digit number by 3.9
176. Multiplying a 2-digit number by 4.1
177. Multiplying a 2-digit number by 4 1/4
178. Multiplying a 2-digit number by 4 1/7
179. Multiplying a 2-digit number by 4 1/6
180. Multiplying a 2-digit number by 4 1/5
181. Multiplying a 2-digit number by 4 2/7
182. Multiplying a 2-digit number by 4.3
183. Multiplying a 2-digit number by 4.4
184. Multiplying a 2-digit number by 4 3/7
185. Multiplying a 2-digit number by 4 4/9
186. Multiplying a 2-digit number by 4 1/2
187. Multiplying a 2-digit number by 4 5/9
188. Multiplying a 2-digit number by 4.6
189. Multiplying a 2-digit number by 4.7
190. Multiplying a 2-digit number by 4 3/4
191. Multiplying a 2-digit number by 4 4/5
192. Multiplying a 2-digit number by 4 5/6
193. Multiplying a 2-digit number by 4 7/8
194. Multiplying a 2-digit number by 5.1
195. Multiplying a 2-digit number by 5 1/8
196. Multiplying a 2-digit number by 5 1/6
197. Multiplying a 2-digit number by 5.2
198. Multiplying a 2-digit number by 5 1/4
199. Multiplying a 2-digit number by 5.3
200. Multiplying a 2-digit number by 5 4/9
201. Multiplying a 2-digit number by 5 1/2
202. Multiplying a 2-digit number by 5 5/9
203. Multiplying a 2-digit number by 5.6
204. Multiplying a 2-digit number by 5.7
205. Multiplying a 2-digit number by 5 4/7
206. Multiplying a 2-digit number by 5 5/7
207. Multiplying a 2-digit number by 5 4/5
208. Multiplying a 2-digit number by 5 6/7
209. Multiplying a 2-digit number by 5.9
210. Multiplying a 2-digit number by 6.1
211. Multiplying a 2-digit number by 6 1/8
212. Multiplying a 2-digit number by 6 1/5
213. Multiplying a 2-digit number by 6 1/4
214. Multiplying a 2-digit number by 6.3
215. Multiplying a 2-digit number by 6 1/3
216. Multiplying a 2-digit number by 6 3/8
217. Multiplying a 2-digit number by 6.4
218. Multiplying a 2-digit number by 6 4/9
219. Multiplying a 2-digit number by 6 1/2
220. Multiplying a 2-digit number by 6 5/9
221. Multiplying a 2-digit number by 6.6
222. Multiplying a 2-digit number by 6 2/3
223. Multiplying a 2-digit number by 6 7/9
224. Multiplying a 2-digit number by 6 5/6
225. Multiplying a 2-digit number by 6 6/7
226. Multiplying a 2-digit number by 6 8/9
227. Multiplying a 2-digit number by 7.1
228. Multiplying a 2-digit number by 7 1/7
229. Multiplying a 2-digit number by 7.2
230. Multiplying a 2-digit number by 7 1/4
231. Multiplying a 2-digit number by 7.3
232. Multiplying a 2-digit number by 7 2/7
233. Multiplying a 2-digit number by 7.4
234. Multiplying a 2-digit number by 7 1/2
235. Multiplying a 2-digit number by 7 3/5
236. Multiplying a 2-digit number by 7.6
237. Multiplying a 2-digit number by 7.7
238. Multiplying a 2-digit number by 7 3/4
239. Multiplying a 2-digit number by 7 4/5
240. Multiplying a 2-digit number by 8.1
241. Multiplying a 2-digit number by 8 1/6
242. Multiplying a 2-digit number by 8.2
243. Multiplying a 2-digit number by 8 2/7
244. Multiplying a 2-digit number by 8.3
245. Multiplying a 2-digit number by 8 1/3
246. Multiplying a 2-digit number by 8 3/7
247. Multiplying a 2-digit number by 8 4/7
248. Multiplying a 2-digit number by 8 1/2
249. Multiplying a 2-digit number by 8.6
250. Multiplying a 2-digit number by 8 5/8
251. Multiplying a 2-digit number by 8 2/3
252. Multiplying a 2-digit number by 8 5/7
253. Multiplying a 2-digit number by 8 7/9
254. Multiplying a 2-digit number by 8 7/8
255. Multiplying a 2-digit number by 8 8/9
256. Multiplying a 2-digit number by 9.1
257. Multiplying a 2-digit number by 9.2
258. Multiplying a 2-digit number by 9.3
259. Multiplying a 2-digit number by 9 1/3
260. Multiplying a 2-digit number by 9.4
261. Multiplying a 2-digit number by 9 1/2 (four steps)
262. Multiplying a 2-digit number by 9 1/2 (two steps)
263. Multiplying a 2-digit number by 9.6
264. Multiplying a 2-digit number by 9 2/3
265. Multiplying a 2-digit number by 9 5/7
266. Multiplying a 2-digit number by 9.7
267. Multiplying a 2-digit number by 9 3/4
268. Multiplying a 2-digit number by 9 7/9
269. Multiplying a 2-digit number by 9 4/5
270. Multiplying a 2-digit number by 9 5/6
271. Multiplying a 2-digit number by 9 6/7
272. Multiplying a 2-digit number by 9 7/8
273. Multiplying a 2-digit number by 9 8/9
274. Multiplying a 2-digit number by 10.1
275. Multiplying a 2-digit number by 10.4
276. Multiplying a 2-digit number by 10.7
277. Multiplying a 2-digit number by 10 1/2
278. Multiplying a 2-digit number by 11 1/2
279. Multiplying a 2-digit number by 12 1/2
280. Multiplying a 2-digit number by 15
281. Multiplying a 2- or 3-digit number by 16 2/3
282. Multiplying a 2-digit number by 18
283. Multiplying a 2-digit number by 19 1/2
284. Multiplying a 2-digit number by 20 1/2
285. Multiplying a 2-digit number by 21
286. Multiplying a 2-digit number by 22
287. Multiplying a 2-digit number by 23
288. Multiplying a 2-digit number by 24
289. Multiplying a 2- or 3-digit number by 25
290. Multiplying a 2-digit number by 26
291. Multiplying a 2-digit number by 27
292. Multiplying a 2-digit number by 28
293. Multiplying a 2-digit number by 29
294. Multiplying a 2-digit number by 29 ½
295. Multiplying a 2-digit number by 30 ½
296. Multiplying a 2-digit number by 31
297. Multiplying a 2-digit number by 32
298. Multiplying a 2-digit number by 33
299. Multiplying a 2-digit number by 33 1/3
300. Multiplying a 2-digit number by 34
301. Multiplying a 2-digit number by 35
302. Multiplying a 2-digit number by 36
303. Multiplying a 2-digit number by 37
304. Multiplying a 2-digit number by 37 1/2
305. Multiplying a 2-digit number by 38
306. Multiplying a 2-digit number by 39
307. Multiplying a 2-digit number by 39 1/2
308. Multiplying a 2-digit number by 40 1/2
309. Multiplying a 2-digit number by 42
310. Multiplying a 2-digit number by 43
311. Multiplying a 2-digit number by 44
312. Multiplying a 2-digit number by 45
313. Multiplying a 2-digit number by 46
314. Multiplying a 2-digit number by 47
315. Multiplying a 2-digit number by 48
316. Multiplying a 2-digit number by 49 (a)
317. Multiplying a 2-digit number by 49 (b)
318. Multiplying a 2-digit number by 49 1/2
319. Multiplying a 2-digit number by 50 1/2
320. Multiplying a 2-digit number by 51
321. Multiplying a 2-digit number by 52
322. Multiplying a 2-digit number by 53
323. Multiplying a 2-digit number by 54
324. Multiplying a 2-digit number by 55 (a)
325. Multiplying a 2-digit number by 55 (b)
326. Multiplying a 2-digit number by 56
327. Multiplying a 2-digit number by 57
328. Multiplying a 2-digit number by 58
329. Multiplying a 2-digit number by 59
330. Multiplying a 2-digit number by 59 1/2
331. Multiplying a 2-digit number by 60 1/2
332. Multiplying a 2-digit number by 61
333. Multiplying a 2-digit number by 62
334. Multiplying a 2-digit number by 63
335. Multiplying a 2-digit number by 64
336. Multiplying a 2-digit number by 65
337. Multiplying a 2-digit number by 66
338. Multiplying a 2-digit number by 67
339. Multiplying a 2-digit number by 68
340. Multiplying a 2-digit number by 69
341. Multiplying a 2-digit number by 69 1/2
342. Multiplying a 2-digit number by 70 1/2
343. Multiplying a 2-digit number by 71
344. Multiplying a 2-digit number by 72
345. Multiplying a 2-digit number by 73
346. Multiplying a 2- or 3-digit number by 75
347. Multiplying a 2-digit number by 76
348. Multiplying a 2-digit number by 77
349. Multiplying a 2-digit number by 78
350. Multiplying a 2-digit number by 79
351. Multiplying a 2-digit number by 79 1/2
352. Multiplying a 2-digit number by 80 1/2
353. Multiplying a 2-digit number by 81
354. Multiplying a 2-digit number by 82
355. Multiplying a 2-digit number by 83
356. Multiplying a 2-digit number by 84
357. Multiplying a 2-digit number by 85
358. Multiplying a 2-digit number by 86
359. Multiplying a 2-digit number by 87
360. Multiplying a 2-digit number by 88
361. Multiplying a 2-digit number by 89
362. Multiplying a 2-digit number by 89 1/2
363. Multiplying a 2-digit number by 90 1/2
364. Multiplying a 2-digit number by 91
365. Multiplying a 2-digit number by 92
366. Multiplying a 2-digit number by 93
367. Multiplying a 2-digit number by 94
368. Multiplying a 2-digit number by 97
369. Multiplying a 2-digit number by 99
370. Multiplying a 3-digit number by 99
371. Multiplying a 2- or 3-digit number by 101
372. Multiplying a 2-digit number by 102 and adding 11
373. Multiplying a 2-digit number by 103 and adding 12
374. Multiplying a 2-digit number by 125
375. Multiplying a 3-digit number by 143
376. Multiplying a 2-digit number by 166 2/3
377. Multiplying a 2-digit number by 198
378. Multiplying a 2-digit number by 201 and adding 11
379. Multiplying a 2-digit number by 202 and adding 11
380. Multiplying a 2-digit number by 250
381. Multiplying a 2-digit number by 297
382. Multiplying a 2-digit number by 375
383. Multiplying a 2-digit number by 396
384. Multiplying a 2-digit number by 495
385. Multiplying a 2-digit number by 594
386. Multiplying a 2-digit number by 625
387. Multiplying a 2-digit number by 693
388. Multiplying a 2-digit number by 792
389. Multiplying a 2-digit number by 875
390. Multiplying a 2-digit number by 891
391. Multiplying a 2-digit number by 999
392. Multiplying a 2- or 3-digit number by 1001 and adding 21 (or 201)
393. Multiplying a 2-, 3-, or 4-digit number by 10001 and adding 21, 201, or 2001
394. Multiplying a 2-, 3-, 4-, or 5-digit number by 100001
395. Multiplying repeating 1's by repeating 9's
396. Multiplying repeating 1's by 12
397. Multiplying repeating 1's by 14
398. Multiplying repeating 1's by 15
399. Multiplying repeating 1's by 16
400. Multiplying repeating 1's by 17
401. Multiplying repeating 1's by 18
402. Multiplying repeating 1's by 19
403. Multiplying repeating 1's by 21
404. Multiplying repeating 1's by 22
405. Multiplying repeating 1's by 24
406. Multiplying repeating 1's by 25
407. Multiplying repeating 1's by 26
408. Multiplying repeating 1's by 27
409. Multiplying repeating 1's by 29
410. Multiplying repeating 1's by 33
411. Multiplying repeating 1's by 41
412. Multiplying repeating 1's by 44
413. Multiplying repeating 1's by 45
414. Multiplying repeating 1's by 55
415. Multiplying repeating 1's by 66
416. Multiplying repeating 1's by 77
417. Multiplying repeating 1's by 88
418. Multiplying repeating 1's by 99
419. Multiplying repeating 1's by 222
420. Multiplying repeating 1's by 333
421. Multiplying repeating 2's by repeating 5's
422. Multiplying repeating 2's by repeating 9's
423. Multiplying repeating 2's by 12
424. Multiplying repeating 2's by 16
425. Multiplying repeating 2's by 17
426. Multiplying repeating 2's by 22
427. Multiplying repeating 2's by 28
428. Multiplying repeating 2's by 33
429. Multiplying repeating 2's by 44
430. Multiplying repeating 2's by 55
431. Multiplying repeating 2's by 66
432. Multiplying repeating 2's by 77
433. Multiplying repeating 2's by 88
434. Multiplying repeating 2's by 99
435. Multiplying repeating 3's by repeating 6's
436. Multiplying repeating 3's by repeating 9's
437. Multiplying repeating 3's by 13
438. Multiplying repeating 3's by 15
439. Multiplying repeating 3's by 23
440. Multiplying repeating 3's by 35
441. Multiplying repeating 3's by 55
442. Multiplying repeating 3's by 66
443. Multiplying repeating 3's by 77
444. Multiplying repeating 3's by 88
445. Multiplying repeating 3's by 99
446. Multiplying repeating 4's by 15
447. Multiplying repeating 4's by 17
448. Multiplying repeating 4's by 22
449. Multiplying repeating 4's by 24
450. Multiplying repeating 4's by 28
451. Multiplying repeating 4's by 31
452. Multiplying repeating 4's by 36
453. Multiplying repeating 4's by 42
454. Multiplying repeating 4's by 44
455. Multiplying repeating 4's by 55
456. Multiplying repeating 4's by 88
457. Multiplying repeating 4's by repeating 3's
458. Multiplying repeating 4's by repeating 5's
459. Multiplying repeating 4's by repeating 9's
460. Multiplying repeating 5's by 25
461. Multiplying repeating 5's by 28
462. Multiplying repeating 5's by 33
463. Multiplying repeating 5's by 45
464. Multiplying repeating 5's by 66
465. Multiplying repeating 5's by 88
466. Multiplying repeating 5's by repeating 9's
467. Multiplying repeating 6's by repeating 9's
468. Multiplying repeating 6's by 16
469. Multiplying repeating 6's by 12
470. Multiplying repeating 6's by 22
471. Multiplying repeating 6's by 31
472. Multiplying repeating 6's by 32
473. Multiplying repeating 6's by 33
474. Multiplying repeating 6's by 43
475. Multiplying repeating 6's by 66
476. Multiplying repeating 6's by 77
477. Multiplying repeating 6's by 88
478. Multiplying repeating 6's by 444
479. Multiplying repeating 6's by 888
480. Multiplying repeating 7's by repeating 9's
481. Multiplying repeating 7's by 17
482. Multiplying repeating 7's by 32
483. Multiplying repeating 7's by 33
484. Multiplying repeating 7's by 42
485. Multiplying repeating 7's by 44
486. Multiplying repeating 7's by 55
487. Multiplying repeating 7's by 88
488. Multiplying repeating 8's by repeating 9's
489. Multiplying repeating 8's by 22
490. Multiplying repeating 8's by 23
491. Multiplying repeating 8's by 29
492. Multiplying repeating 8's by 36
493. Multiplying repeating 8's by 44
494. Multiplying repeating 8's by 55
495. Multiplying repeating 8's by 66
496. Multiplying repeating 8's by 88
497. Multiplying repeating 9's by 14
498. Multiplying repeating 9's by 22
499. Multiplying repeating 9's by 25
500. Multiplying repeating 9's by 27
501. Multiplying repeating 9's by 33
502. Multiplying repeating 9's by 44
503. Multiplying repeating 9's by 55
504. Multiplying repeating 9's by 77
505. Multiplying repeating 9's by 99
506. Multiplying a repeating 3-digit number by 2, then dividing it by 37
507. Multiplying a repeating 3-digit number by 5, then dividing it by 37
508. Multiplying a repeating 9-digit number by 3, then dividing it by 12345679
509. Multiplying a multi-digit number by 8 and adding the last digit
510. Multiplying a number sequence by 8, adding a number, and subtracting 20
511. Multiply integer + 1/2 times the number +1
512. Multiplying the sum and the difference of a 2-digit and a 1-digit number
513. Multiplying two mixed numbers
514. Multiplying two mixed numbers with fractions adding to 1
515. Multiplying a 4-digit number by 99
516. Multiplying a 4-digit number by 137 and 73; subtracting 1200
517. Multiplying a 5-digit number by 9091 and 11; subtracting 1200

     Dividing Numbers

518. Dividing a number by 0.125
519. Dividing a 2-digit number by 1 1/9
520. Dividing a 2-digit number by 1 1/8
521. Dividing a 2-digit number by 1 1/7
522. Dividing a 2-digit number by 1 1/6
523. Dividing a 2-digit number by 1 1/5
524. Dividing a 2-digit number by 1 1/4
525. Dividing a 2-digit number by 1 2/7
526. Dividing a 2-digit number by 1 1/3
527. Dividing a 2-digit number by 1 2/5
528. Dividing a 2-digit number by 1 3/7
529. Dividing a 2-digit number by 1 1/2
530. Dividing a 2-digit number by 1 3/5
531. Dividing a 2-digit number by 1 2/3
532. Dividing a 2-digit number by 1 3/4
533. Dividing a 2-digit number by 1 4/5
534. Dividing a 2-digit number by 2 2/9
535. Dividing a 2-digit number by 2 1/4
536. Dividing a 2-digit number by 2 1/3
537. Dividing a 2- or 3-digit number by 2 1/2
538. Dividing a 2-digit number by 2 2/3
539. Dividing a 2-digit number by 2 6/7
540. Dividing a 2-digit number by 3 1/8
541. Dividing a 2- or 3-digit number by 3 1/3
542. Dividing a 2-digit number by 3 1/2
543. Dividing a 2-digit number by 3 4/7
544. Dividing a 2-digit number by 4 1/6
545. Dividing a 2-digit number by 4 2/7
546. Dividing a 2-digit number by 4 4/9
547. Dividing a 2-digit number by 4 1/2
548. Dividing a 2-digit number by 5 5/7
549. Dividing a 2-digit number by 6 1/4
550. Dividing a 2-digit number by 6 2/3
551. Dividing a 2-digit number by 7 1/7
552. Dividing a 2-digit number by 7 2/7
553. Dividing a 2-digit number by 7 1/2
554. Dividing a 2-digit number by 8 1/3
555. Dividing a 2-digit number by 8 4/7
556. Dividing a 2-digit number by 12 1/2
557. Dividing a 2-digit number by 15
558. Dividing a 2- or 3-digit number by 16 2/3
559. Dividing a 2- or 3-digit number by 25
560. Dividing a 2- or 3-digit number by 33 1/3
561. Dividing a 2- or 3-digit number by 35
562. Dividing a 2-digit number by 37 1/2
563. Dividing a 2-digit number by 40
564. Dividing a 2-digit number by 45
565. Dividing a 2-digit number by 50
566. Dividing a 2-digit number by 62 1/2
567. Dividing a 2- or 3-digit number by 66 2/3
568. Dividing a 2- or 3-digit number by 75
569. Dividing a 2-digit number by 83 1/3
570. Dividing a 2-digit number by 87 1/2
571. Dividing a 2-digit number by 125
572. Dividing a 2-digit number by 166 2/3
573. Dividing a 2-digit number by 250
574. Dividing a 2- or 3-digit number by 333 1/3
575. Dividing a 2-digit number by 375
576. Dividing a 2-digit number by 625
577. Dividing a 2-digit number by 875
578. Dividing a repeating 3-digit number by 37 and adding 41
579. Dividing a repeating 6-digit number by 15873
580. Dividing a repeating 6-digit number by 7, then by 13
581. Dividing a repeating 6-digit number by 13, then by 11
582. Dividing a repeating 6-digit number by 7, 11, and 13, then subtracting 101
583. Dividing a repeating 6-digit number by 37037, then multiplying by 5
584. Dividing mixed numbers by 2
585. Finding the difference of the squares of two consecutive 2-digit numbers
586. Finding the difference of the squares of two different 2-digit numbers
587. Finding the square root of squares of 2-digit numbers ending in 1
588. Finding the square root of a perfect square ending in 5

     Adding Numbers

589. Finding the sum of all even numbers from 2 through a selected 2-digit even number
590. Finding the sum of the digits of the square of repeating ones
591. Adding a sequence of consecutive odd numbers
592. Adding consecutive numbers between two numbers
593. Adding a sequence of numbers from one to a selected 2-digit number
594. Adding a sequence of numbers from one to a selected 1-digit number and back
595. Adding sequences of numbers in the 10's
596. Adding sequences of numbers in the 20's
597. Adding sequences of numbers in the 30's
598. Adding sequences of numbers in the 40's
599. Adding sequences of numbers in the 50's
600. Adding sequences of numbers in the 60's
601. Adding sequences of numbers in the 70's
602. Adding sequences of numbers in the 80's
603. Adding a series of doubles
604. Adding a series of quadruples
605. Adding a series of ten numbers

     Subtracting Numbers

606. Subtracting from a repeating 1's number, dividing by 9, subtracting 21
607. Subtracting from a repeating 8's number, dividing by 9, subtracting 10
608. Subtracting the squares of two numbers
609. Reversing/adding/subtracting 3-digit numbers

     Finding Percentages

610. Finding 2.5 percent of a number
611. Finding 5 percent of a number
612. Finding 15 percent of a number
613. Finding 20 percent of a number
614. Finding 25 percent of a number
615. Finding 33 1/3 percent of a number
616. Finding 40 percent of a number
617. Finding 45 percent of a number
618. Finding 55 percent of a number
619. Finding 70 percent of a number
620. Finding 75 percent of a number

     Calculation Practice Exercises