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 May 21 2026
04:28:38 PM | Thursday May 21 2026
04:28:38 PMFlip Answers |
| 1) | 107 * 93 = | | 1) 100 * 100 - 7 * 7 = 9951 |
| 2) | 293 * 307 = | | 2) 300 * 300 - 7 * 7 = 89951 |
| 3) | 398 * 402 = | | 3) 400 * 400 - 2 * 2 = 159996 |
| 4) | 305 * 295 = | | 4) 300 * 300 - 5 * 5 = 89975 |
| 5) | 396 * 404 = | | 5) 400 * 400 - 4 * 4 = 159984 |
| 6) | 297 * 303 = | | 6) 300 * 300 - 3 * 3 = 89991 |
| 7) | 401 * 399 = | | 7) 400 * 400 - 1 * 1 = 159999 |
| 8) | 94 * 106 = | | 8) 100 * 100 - 6 * 6 = 9964 |
| 9) | 98 * 102 = | | 9) 100 * 100 - 2 * 2 = 9996 |
| 10) | 110 * 90 = | | 10) 100 * 100 - 10 * 10 = 9900 |
| 11) | 74 * 42 + 74 * 58 = | | 11) ( 58 + 42) * 74 = 7400 |
| 12) | 40 * 42 + 40 * 58 = | | 12) ( 42 + 58) * 40 = 4000 |
| 13) | 254 * 36 - 36 * 54 = | | 13) ( 254 - 54) * 36 = 7200 |
| 14) | 56 * 97 + 44 * 97 = | | 14) ( 44 + 56) * 97 = 9700 |
| 15) | 166 * 91 - 66 * 91 = | | 15) ( 166 - 66) * 91 = 9100 |
| 16) | 42 * 83 + 58 * 83 = | | 16) ( 58 + 42) * 83 = 8300 |
| 17) | 32 * 273 - 32 * 73 = | | 17) ( 273 - 73) * 32 = 6400 |
| 18) | 21 * 152 - 52 * 21 = | | 18) ( 152 - 52) * 21 = 2100 |
| 19) | 53 * 141 - 53 * 41 = | | 19) ( 141 - 41) * 53 = 5300 |
| 20) | 156 * 35 - 56 * 35 = | | 20) ( 156 - 56) * 35 = 3500 |
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Score: ______________ | |
