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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Thursday November 27 2025
05:09:04 AM | Thursday November 27 2025
05:09:04 AMFlip Answers |
| 1) | 409 * 391 = | | 1) 400 * 400 - 9 * 9 = 159919 |
| 2) | 96 * 104 = | | 2) 100 * 100 - 4 * 4 = 9984 |
| 3) | 303 * 297 = | | 3) 300 * 300 - 3 * 3 = 89991 |
| 4) | 94 * 106 = | | 4) 100 * 100 - 6 * 6 = 9964 |
| 5) | 307 * 293 = | | 5) 300 * 300 - 7 * 7 = 89951 |
| 6) | 207 * 193 = | | 6) 200 * 200 - 7 * 7 = 39951 |
| 7) | 109 * 91 = | | 7) 100 * 100 - 9 * 9 = 9919 |
| 8) | 410 * 390 = | | 8) 400 * 400 - 10 * 10 = 159900 |
| 9) | 290 * 310 = | | 9) 300 * 300 - 10 * 10 = 89900 |
| 10) | 210 * 190 = | | 10) 200 * 200 - 10 * 10 = 39900 |
| 11) | 73 * 97 + 27 * 97 = | | 11) ( 27 + 73) * 97 = 9700 |
| 12) | 34 * 66 + 34 * 34 = | | 12) ( 34 + 66) * 34 = 3400 |
| 13) | 71 * 49 + 71 * 51 = | | 13) ( 49 + 51) * 71 = 7100 |
| 14) | 61 * 88 + 39 * 88 = | | 14) ( 39 + 61) * 88 = 8800 |
| 15) | 60 * 153 - 53 * 60 = | | 15) ( 153 - 53) * 60 = 6000 |
| 16) | 63 * 57 + 43 * 63 = | | 16) ( 57 + 43) * 63 = 6300 |
| 17) | 173 * 27 - 27 * 73 = | | 17) ( 173 - 73) * 27 = 2700 |
| 18) | 59 * 57 + 43 * 59 = | | 18) ( 43 + 57) * 59 = 5900 |
| 19) | 57 * 246 - 57 * 46 = | | 19) ( 246 - 46) * 57 = 11400 |
| 20) | 47 * 60 + 47 * 140 = | | 20) ( 140 + 60) * 47 = 9400 |
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Score: ______________ | |
