Math Main Page => Exercises - Math III
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Goal: to practice how to make use of distributive property on special numbers, like (A + B) * (A - B) = A*A - B*B, A*C +B*C = (A + B ) *C, A*C - B*C = (A-B) * C
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Tuesday June 09 2026
11:05:28 PM | Tuesday June 09 2026
11:05:28 PMFlip Answers |
| 1) | 99 * 101 = | | 1) 100 * 100 - 1 * 1 = 9999 |
| 2) | 203 * 197 = | | 2) 200 * 200 - 3 * 3 = 39991 |
| 3) | 397 * 403 = | | 3) 400 * 400 - 3 * 3 = 159991 |
| 4) | 191 * 209 = | | 4) 200 * 200 - 9 * 9 = 39919 |
| 5) | 296 * 304 = | | 5) 300 * 300 - 4 * 4 = 89984 |
| 6) | 291 * 309 = | | 6) 300 * 300 - 9 * 9 = 89919 |
| 7) | 393 * 407 = | | 7) 400 * 400 - 7 * 7 = 159951 |
| 8) | 191 * 209 = | | 8) 200 * 200 - 9 * 9 = 39919 |
| 9) | 293 * 307 = | | 9) 300 * 300 - 7 * 7 = 89951 |
| 10) | 402 * 398 = | | 10) 400 * 400 - 2 * 2 = 159996 |
| 11) | 70 * 69 + 70 * 131 = | | 11) ( 131 + 69) * 70 = 14000 |
| 12) | 248 * 85 - 48 * 85 = | | 12) ( 248 - 48) * 85 = 17000 |
| 13) | 52 * 270 - 52 * 70 = | | 13) ( 270 - 70) * 52 = 10400 |
| 14) | 253 * 97 - 53 * 97 = | | 14) ( 253 - 53) * 97 = 19400 |
| 15) | 155 * 96 + 96 * 45 = | | 15) ( 155 + 45) * 96 = 19200 |
| 16) | 267 * 43 - 67 * 43 = | | 16) ( 267 - 67) * 43 = 8600 |
| 17) | 74 * 263 - 74 * 63 = | | 17) ( 263 - 63) * 74 = 14800 |
| 18) | 89 * 164 - 89 * 64 = | | 18) ( 164 - 64) * 89 = 8900 |
| 19) | 235 * 25 - 35 * 25 = | | 19) ( 235 - 35) * 25 = 5000 |
| 20) | 30 * 59 + 141 * 30 = | | 20) ( 141 + 59) * 30 = 6000 |
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Score: ______________ | |
