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 May 30 2026
02:26:01 PM | Saturday May 30 2026
02:26:01 PMFlip Answers |
| 1) | 393 * 407 = | | 1) 400 * 400 - 7 * 7 = 159951 |
| 2) | 398 * 402 = | | 2) 400 * 400 - 2 * 2 = 159996 |
| 3) | 398 * 402 = | | 3) 400 * 400 - 2 * 2 = 159996 |
| 4) | 196 * 204 = | | 4) 200 * 200 - 4 * 4 = 39984 |
| 5) | 96 * 104 = | | 5) 100 * 100 - 4 * 4 = 9984 |
| 6) | 94 * 106 = | | 6) 100 * 100 - 6 * 6 = 9964 |
| 7) | 201 * 199 = | | 7) 200 * 200 - 1 * 1 = 39999 |
| 8) | 90 * 110 = | | 8) 100 * 100 - 10 * 10 = 9900 |
| 9) | 99 * 101 = | | 9) 100 * 100 - 1 * 1 = 9999 |
| 10) | 197 * 203 = | | 10) 200 * 200 - 3 * 3 = 39991 |
| 11) | 39 * 71 + 39 * 129 = | | 11) ( 129 + 71) * 39 = 7800 |
| 12) | 82 * 40 + 82 * 160 = | | 12) ( 160 + 40) * 82 = 16400 |
| 13) | 45 * 142 - 45 * 42 = | | 13) ( 142 - 42) * 45 = 4500 |
| 14) | 85 * 37 + 63 * 85 = | | 14) ( 37 + 63) * 85 = 8500 |
| 15) | 170 * 49 - 70 * 49 = | | 15) ( 170 - 70) * 49 = 4900 |
| 16) | 266 * 24 - 24 * 66 = | | 16) ( 266 - 66) * 24 = 4800 |
| 17) | 66 * 51 + 134 * 51 = | | 17) ( 134 + 66) * 51 = 10200 |
| 18) | 25 * 163 + 25 * 37 = | | 18) ( 163 + 37) * 25 = 5000 |
| 19) | 89 * 48 + 152 * 89 = | | 19) ( 152 + 48) * 89 = 17800 |
| 20) | 25 * 32 + 25 * 68 = | | 20) ( 32 + 68) * 25 = 2500 |
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Score: ______________ | |
