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 April 18 2026
02:55:43 AM | Saturday April 18 2026
02:55:43 AMFlip Answers |
| 1) | 393 * 407 = | | 1) 400 * 400 - 7 * 7 = 159951 |
| 2) | 110 * 90 = | | 2) 100 * 100 - 10 * 10 = 9900 |
| 3) | 204 * 196 = | | 3) 200 * 200 - 4 * 4 = 39984 |
| 4) | 295 * 305 = | | 4) 300 * 300 - 5 * 5 = 89975 |
| 5) | 199 * 201 = | | 5) 200 * 200 - 1 * 1 = 39999 |
| 6) | 206 * 194 = | | 6) 200 * 200 - 6 * 6 = 39964 |
| 7) | 90 * 110 = | | 7) 100 * 100 - 10 * 10 = 9900 |
| 8) | 399 * 401 = | | 8) 400 * 400 - 1 * 1 = 159999 |
| 9) | 97 * 103 = | | 9) 100 * 100 - 3 * 3 = 9991 |
| 10) | 294 * 306 = | | 10) 300 * 300 - 6 * 6 = 89964 |
| 11) | 268 * 45 - 45 * 68 = | | 11) ( 268 - 68) * 45 = 9000 |
| 12) | 42 * 139 - 42 * 39 = | | 12) ( 139 - 39) * 42 = 4200 |
| 13) | 66 * 169 - 66 * 69 = | | 13) ( 169 - 69) * 66 = 6600 |
| 14) | 74 * 144 + 74 * 56 = | | 14) ( 144 + 56) * 74 = 14800 |
| 15) | 141 * 73 + 73 * 59 = | | 15) ( 141 + 59) * 73 = 14600 |
| 16) | 143 * 68 + 68 * 57 = | | 16) ( 143 + 57) * 68 = 13600 |
| 17) | 260 * 61 - 61 * 60 = | | 17) ( 260 - 60) * 61 = 12200 |
| 18) | 264 * 29 - 29 * 64 = | | 18) ( 264 - 64) * 29 = 5800 |
| 19) | 69 * 96 + 31 * 96 = | | 19) ( 31 + 69) * 96 = 9600 |
| 20) | 249 * 56 - 49 * 56 = | | 20) ( 249 - 49) * 56 = 11200 |
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Score: ______________ | |
