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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Wednesday August 12 2026
05:29:00 PM | Wednesday August 12 2026
05:29:00 PMFlip Answers |
| 1) | 394 * 406 = | | 1) 400 * 400 - 6 * 6 = 159964 |
| 2) | 308 * 292 = | | 2) 300 * 300 - 8 * 8 = 89936 |
| 3) | 390 * 410 = | | 3) 400 * 400 - 10 * 10 = 159900 |
| 4) | 107 * 93 = | | 4) 100 * 100 - 7 * 7 = 9951 |
| 5) | 99 * 101 = | | 5) 100 * 100 - 1 * 1 = 9999 |
| 6) | 394 * 406 = | | 6) 400 * 400 - 6 * 6 = 159964 |
| 7) | 308 * 292 = | | 7) 300 * 300 - 8 * 8 = 89936 |
| 8) | 308 * 292 = | | 8) 300 * 300 - 8 * 8 = 89936 |
| 9) | 302 * 298 = | | 9) 300 * 300 - 2 * 2 = 89996 |
| 10) | 204 * 196 = | | 10) 200 * 200 - 4 * 4 = 39984 |
| 11) | 81 * 142 - 81 * 42 = | | 11) ( 142 - 42) * 81 = 8100 |
| 12) | 59 * 158 - 59 * 58 = | | 12) ( 158 - 58) * 59 = 5900 |
| 13) | 90 * 50 + 50 * 90 = | | 13) ( 50 + 50) * 90 = 9000 |
| 14) | 28 * 238 - 38 * 28 = | | 14) ( 238 - 38) * 28 = 5600 |
| 15) | 88 * 270 - 88 * 70 = | | 15) ( 270 - 70) * 88 = 17600 |
| 16) | 129 * 92 + 71 * 92 = | | 16) ( 129 + 71) * 92 = 18400 |
| 17) | 36 * 235 - 36 * 35 = | | 17) ( 235 - 35) * 36 = 7200 |
| 18) | 82 * 136 + 64 * 82 = | | 18) ( 136 + 64) * 82 = 16400 |
| 19) | 243 * 33 - 43 * 33 = | | 19) ( 243 - 43) * 33 = 6600 |
| 20) | 261 * 73 - 61 * 73 = | | 20) ( 261 - 61) * 73 = 14600 |
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Score: ______________ | |
