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 December 02 2025
01:42:05 PM | Tuesday December 02 2025
01:42:05 PMFlip Answers |
| 1) | 109 * 91 = | | 1) 100 * 100 - 9 * 9 = 9919 |
| 2) | 297 * 303 = | | 2) 300 * 300 - 3 * 3 = 89991 |
| 3) | 310 * 290 = | | 3) 300 * 300 - 10 * 10 = 89900 |
| 4) | 193 * 207 = | | 4) 200 * 200 - 7 * 7 = 39951 |
| 5) | 104 * 96 = | | 5) 100 * 100 - 4 * 4 = 9984 |
| 6) | 95 * 105 = | | 6) 100 * 100 - 5 * 5 = 9975 |
| 7) | 396 * 404 = | | 7) 400 * 400 - 4 * 4 = 159984 |
| 8) | 95 * 105 = | | 8) 100 * 100 - 5 * 5 = 9975 |
| 9) | 96 * 104 = | | 9) 100 * 100 - 4 * 4 = 9984 |
| 10) | 403 * 397 = | | 10) 400 * 400 - 3 * 3 = 159991 |
| 11) | 255 * 34 - 55 * 34 = | | 11) ( 255 - 55) * 34 = 6800 |
| 12) | 72 * 29 + 29 * 128 = | | 12) ( 128 + 72) * 29 = 5800 |
| 13) | 64 * 82 + 36 * 82 = | | 13) ( 64 + 36) * 82 = 8200 |
| 14) | 71 * 33 + 67 * 71 = | | 14) ( 33 + 67) * 71 = 7100 |
| 15) | 80 * 35 + 65 * 80 = | | 15) ( 35 + 65) * 80 = 8000 |
| 16) | 38 * 253 - 53 * 38 = | | 16) ( 253 - 53) * 38 = 7600 |
| 17) | 48 * 128 + 48 * 72 = | | 17) ( 128 + 72) * 48 = 9600 |
| 18) | 73 * 68 + 127 * 68 = | | 18) ( 127 + 73) * 68 = 13600 |
| 19) | 72 * 59 + 128 * 59 = | | 19) ( 128 + 72) * 59 = 11800 |
| 20) | 46 * 167 - 67 * 46 = | | 20) ( 167 - 67) * 46 = 4600 |
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Score: ______________ | |
