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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Sunday August 23 2026
05:00:40 AM | Sunday August 23 2026
05:00:40 AMFlip Answers |
| 1) | 408 * 392 = | | 1) 400 * 400 - 8 * 8 = 159936 |
| 2) | 110 * 90 = | | 2) 100 * 100 - 10 * 10 = 9900 |
| 3) | 201 * 199 = | | 3) 200 * 200 - 1 * 1 = 39999 |
| 4) | 204 * 196 = | | 4) 200 * 200 - 4 * 4 = 39984 |
| 5) | 297 * 303 = | | 5) 300 * 300 - 3 * 3 = 89991 |
| 6) | 401 * 399 = | | 6) 400 * 400 - 1 * 1 = 159999 |
| 7) | 101 * 99 = | | 7) 100 * 100 - 1 * 1 = 9999 |
| 8) | 92 * 108 = | | 8) 100 * 100 - 8 * 8 = 9936 |
| 9) | 207 * 193 = | | 9) 200 * 200 - 7 * 7 = 39951 |
| 10) | 207 * 193 = | | 10) 200 * 200 - 7 * 7 = 39951 |
| 11) | 251 * 81 - 51 * 81 = | | 11) ( 251 - 51) * 81 = 16200 |
| 12) | 150 * 82 - 50 * 82 = | | 12) ( 150 - 50) * 82 = 8200 |
| 13) | 70 * 70 + 70 * 130 = | | 13) ( 130 + 70) * 70 = 14000 |
| 14) | 133 * 55 + 55 * 67 = | | 14) ( 133 + 67) * 55 = 11000 |
| 15) | 147 * 28 - 47 * 28 = | | 15) ( 147 - 47) * 28 = 2800 |
| 16) | 52 * 62 + 48 * 62 = | | 16) ( 52 + 48) * 62 = 6200 |
| 17) | 63 * 126 + 74 * 63 = | | 17) ( 126 + 74) * 63 = 12600 |
| 18) | 29 * 158 - 58 * 29 = | | 18) ( 158 - 58) * 29 = 2900 |
| 19) | 24 * 242 - 42 * 24 = | | 19) ( 242 - 42) * 24 = 4800 |
| 20) | 273 * 71 - 71 * 73 = | | 20) ( 273 - 73) * 71 = 14200 |
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Score: ______________ | |
