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 February 04 2026
04:14:19 AM | Wednesday February 04 2026
04:14:19 AMFlip Answers |
| 1) | 91 * 109 = | | 1) 100 * 100 - 9 * 9 = 9919 |
| 2) | 94 * 106 = | | 2) 100 * 100 - 6 * 6 = 9964 |
| 3) | 298 * 302 = | | 3) 300 * 300 - 2 * 2 = 89996 |
| 4) | 99 * 101 = | | 4) 100 * 100 - 1 * 1 = 9999 |
| 5) | 104 * 96 = | | 5) 100 * 100 - 4 * 4 = 9984 |
| 6) | 397 * 403 = | | 6) 400 * 400 - 3 * 3 = 159991 |
| 7) | 406 * 394 = | | 7) 400 * 400 - 6 * 6 = 159964 |
| 8) | 190 * 210 = | | 8) 200 * 200 - 10 * 10 = 39900 |
| 9) | 409 * 391 = | | 9) 400 * 400 - 9 * 9 = 159919 |
| 10) | 310 * 290 = | | 10) 300 * 300 - 10 * 10 = 89900 |
| 11) | 51 * 84 + 149 * 84 = | | 11) ( 149 + 51) * 84 = 16800 |
| 12) | 56 * 48 + 56 * 52 = | | 12) ( 48 + 52) * 56 = 5600 |
| 13) | 30 * 244 - 30 * 44 = | | 13) ( 244 - 44) * 30 = 6000 |
| 14) | 127 * 30 + 73 * 30 = | | 14) ( 127 + 73) * 30 = 6000 |
| 15) | 172 * 34 - 72 * 34 = | | 15) ( 172 - 72) * 34 = 3400 |
| 16) | 257 * 33 - 57 * 33 = | | 16) ( 257 - 57) * 33 = 6600 |
| 17) | 61 * 25 + 25 * 139 = | | 17) ( 139 + 61) * 25 = 5000 |
| 18) | 82 * 169 - 82 * 69 = | | 18) ( 169 - 69) * 82 = 8200 |
| 19) | 95 * 63 + 95 * 37 = | | 19) ( 63 + 37) * 95 = 9500 |
| 20) | 242 * 42 - 42 * 42 = | | 20) ( 242 - 42) * 42 = 8400 |
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Score: ______________ | |
