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 July 16 2026
08:40:20 AM | Thursday July 16 2026
08:40:20 AMFlip Answers |
| 1) | 407 * 393 = | | 1) 400 * 400 - 7 * 7 = 159951 |
| 2) | 390 * 410 = | | 2) 400 * 400 - 10 * 10 = 159900 |
| 3) | 396 * 404 = | | 3) 400 * 400 - 4 * 4 = 159984 |
| 4) | 192 * 208 = | | 4) 200 * 200 - 8 * 8 = 39936 |
| 5) | 305 * 295 = | | 5) 300 * 300 - 5 * 5 = 89975 |
| 6) | 105 * 95 = | | 6) 100 * 100 - 5 * 5 = 9975 |
| 7) | 199 * 201 = | | 7) 200 * 200 - 1 * 1 = 39999 |
| 8) | 199 * 201 = | | 8) 200 * 200 - 1 * 1 = 39999 |
| 9) | 101 * 99 = | | 9) 100 * 100 - 1 * 1 = 9999 |
| 10) | 292 * 308 = | | 10) 300 * 300 - 8 * 8 = 89936 |
| 11) | 86 * 159 - 86 * 59 = | | 11) ( 159 - 59) * 86 = 8600 |
| 12) | 47 * 62 + 47 * 138 = | | 12) ( 138 + 62) * 47 = 9400 |
| 13) | 30 * 69 + 30 * 131 = | | 13) ( 131 + 69) * 30 = 6000 |
| 14) | 144 * 76 + 56 * 76 = | | 14) ( 144 + 56) * 76 = 15200 |
| 15) | 42 * 139 - 39 * 42 = | | 15) ( 139 - 39) * 42 = 4200 |
| 16) | 62 * 83 + 138 * 83 = | | 16) ( 138 + 62) * 83 = 16600 |
| 17) | 274 * 22 - 22 * 74 = | | 17) ( 274 - 74) * 22 = 4400 |
| 18) | 94 * 161 - 61 * 94 = | | 18) ( 161 - 61) * 94 = 9400 |
| 19) | 44 * 39 + 56 * 39 = | | 19) ( 56 + 44) * 39 = 3900 |
| 20) | 79 * 41 + 59 * 79 = | | 20) ( 59 + 41) * 79 = 7900 |
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Score: ______________ | |
