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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Saturday September 12 2026
09:17:59 PM | Saturday September 12 2026
09:17:59 PMFlip Answers |
| 1) | 303 * 297 = | | 1) 300 * 300 - 3 * 3 = 89991 |
| 2) | 393 * 407 = | | 2) 400 * 400 - 7 * 7 = 159951 |
| 3) | 209 * 191 = | | 3) 200 * 200 - 9 * 9 = 39919 |
| 4) | 392 * 408 = | | 4) 400 * 400 - 8 * 8 = 159936 |
| 5) | 302 * 298 = | | 5) 300 * 300 - 2 * 2 = 89996 |
| 6) | 297 * 303 = | | 6) 300 * 300 - 3 * 3 = 89991 |
| 7) | 98 * 102 = | | 7) 100 * 100 - 2 * 2 = 9996 |
| 8) | 402 * 398 = | | 8) 400 * 400 - 2 * 2 = 159996 |
| 9) | 96 * 104 = | | 9) 100 * 100 - 4 * 4 = 9984 |
| 10) | 90 * 110 = | | 10) 100 * 100 - 10 * 10 = 9900 |
| 11) | 87 * 272 - 72 * 87 = | | 11) ( 272 - 72) * 87 = 17400 |
| 12) | 55 * 29 + 45 * 29 = | | 12) ( 55 + 45) * 29 = 2900 |
| 13) | 89 * 258 - 89 * 58 = | | 13) ( 258 - 58) * 89 = 17800 |
| 14) | 39 * 241 - 39 * 41 = | | 14) ( 241 - 41) * 39 = 7800 |
| 15) | 70 * 270 - 70 * 70 = | | 15) ( 270 - 70) * 70 = 14000 |
| 16) | 54 * 66 + 46 * 66 = | | 16) ( 46 + 54) * 66 = 6600 |
| 17) | 52 * 51 + 52 * 149 = | | 17) ( 149 + 51) * 52 = 10400 |
| 18) | 71 * 68 + 32 * 71 = | | 18) ( 32 + 68) * 71 = 7100 |
| 19) | 29 * 271 - 29 * 71 = | | 19) ( 271 - 71) * 29 = 5800 |
| 20) | 71 * 35 + 35 * 29 = | | 20) ( 29 + 71) * 35 = 3500 |
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Score: ______________ | |
