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 14 2026 06:29:25 PM | Thursday May 14 2026 06:29:25 PMFlip Answers |
| 1) | 303 * 297 = | | 1) 300 * 300 - 3 * 3 = 89991 |
| 2) | 392 * 408 = | | 2) 400 * 400 - 8 * 8 = 159936 |
| 3) | 407 * 393 = | | 3) 400 * 400 - 7 * 7 = 159951 |
| 4) | 193 * 207 = | | 4) 200 * 200 - 7 * 7 = 39951 |
| 5) | 394 * 406 = | | 5) 400 * 400 - 6 * 6 = 159964 |
| 6) | 310 * 290 = | | 6) 300 * 300 - 10 * 10 = 89900 |
| 7) | 410 * 390 = | | 7) 400 * 400 - 10 * 10 = 159900 |
| 8) | 102 * 98 = | | 8) 100 * 100 - 2 * 2 = 9996 |
| 9) | 308 * 292 = | | 9) 300 * 300 - 8 * 8 = 89936 |
| 10) | 402 * 398 = | | 10) 400 * 400 - 2 * 2 = 159996 |
| 11) | 244 * 83 - 44 * 83 = | | 11) ( 244 - 44) * 83 = 16600 |
| 12) | 60 * 71 + 29 * 60 = | | 12) ( 29 + 71) * 60 = 6000 |
| 13) | 158 * 28 + 42 * 28 = | | 13) ( 158 + 42) * 28 = 5600 |
| 14) | 135 * 94 + 65 * 94 = | | 14) ( 135 + 65) * 94 = 18800 |
| 15) | 96 * 149 + 96 * 51 = | | 15) ( 149 + 51) * 96 = 19200 |
| 16) | 63 * 58 + 37 * 58 = | | 16) ( 37 + 63) * 58 = 5800 |
| 17) | 83 * 125 + 83 * 75 = | | 17) ( 125 + 75) * 83 = 16600 |
| 18) | 97 * 159 - 59 * 97 = | | 18) ( 159 - 59) * 97 = 9700 |
| 19) | 53 * 81 + 47 * 81 = | | 19) ( 53 + 47) * 81 = 8100 |
| 20) | 37 * 63 + 137 * 37 = | | 20) ( 137 + 63) * 37 = 7400 |
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Score: ______________ | |