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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Tuesday April 21 2026
09:15:05 PM | Tuesday April 21 2026
09:15:05 PMFlip Answers |
| 1) | 90 * 110 = | | 1) 100 * 100 - 10 * 10 = 9900 |
| 2) | 192 * 208 = | | 2) 200 * 200 - 8 * 8 = 39936 |
| 3) | 106 * 94 = | | 3) 100 * 100 - 6 * 6 = 9964 |
| 4) | 110 * 90 = | | 4) 100 * 100 - 10 * 10 = 9900 |
| 5) | 96 * 104 = | | 5) 100 * 100 - 4 * 4 = 9984 |
| 6) | 397 * 403 = | | 6) 400 * 400 - 3 * 3 = 159991 |
| 7) | 405 * 395 = | | 7) 400 * 400 - 5 * 5 = 159975 |
| 8) | 202 * 198 = | | 8) 200 * 200 - 2 * 2 = 39996 |
| 9) | 409 * 391 = | | 9) 400 * 400 - 9 * 9 = 159919 |
| 10) | 303 * 297 = | | 10) 300 * 300 - 3 * 3 = 89991 |
| 11) | 267 * 73 - 73 * 67 = | | 11) ( 267 - 67) * 73 = 14600 |
| 12) | 38 * 23 + 23 * 62 = | | 12) ( 38 + 62) * 23 = 2300 |
| 13) | 169 * 84 - 69 * 84 = | | 13) ( 169 - 69) * 84 = 8400 |
| 14) | 53 * 142 - 42 * 53 = | | 14) ( 142 - 42) * 53 = 5300 |
| 15) | 138 * 72 + 62 * 72 = | | 15) ( 138 + 62) * 72 = 14400 |
| 16) | 39 * 156 - 56 * 39 = | | 16) ( 156 - 56) * 39 = 3900 |
| 17) | 44 * 61 + 61 * 56 = | | 17) ( 44 + 56) * 61 = 6100 |
| 18) | 30 * 49 + 30 * 51 = | | 18) ( 51 + 49) * 30 = 3000 |
| 19) | 76 * 141 - 76 * 41 = | | 19) ( 141 - 41) * 76 = 7600 |
| 20) | 79 * 71 + 79 * 29 = | | 20) ( 29 + 71) * 79 = 7900 |
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Score: ______________ | |
