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 December 31 2025
12:52:27 AM | Wednesday December 31 2025
12:52:27 AMFlip Answers |
| 1) | 393 * 407 = | | 1) 400 * 400 - 7 * 7 = 159951 |
| 2) | 295 * 305 = | | 2) 300 * 300 - 5 * 5 = 89975 |
| 3) | 303 * 297 = | | 3) 300 * 300 - 3 * 3 = 89991 |
| 4) | 194 * 206 = | | 4) 200 * 200 - 6 * 6 = 39964 |
| 5) | 108 * 92 = | | 5) 100 * 100 - 8 * 8 = 9936 |
| 6) | 198 * 202 = | | 6) 200 * 200 - 2 * 2 = 39996 |
| 7) | 104 * 96 = | | 7) 100 * 100 - 4 * 4 = 9984 |
| 8) | 90 * 110 = | | 8) 100 * 100 - 10 * 10 = 9900 |
| 9) | 291 * 309 = | | 9) 300 * 300 - 9 * 9 = 89919 |
| 10) | 296 * 304 = | | 10) 300 * 300 - 4 * 4 = 89984 |
| 11) | 158 * 71 + 71 * 42 = | | 11) ( 158 + 42) * 71 = 14200 |
| 12) | 151 * 74 + 74 * 49 = | | 12) ( 151 + 49) * 74 = 14800 |
| 13) | 239 * 34 - 39 * 34 = | | 13) ( 239 - 39) * 34 = 6800 |
| 14) | 72 * 129 + 71 * 72 = | | 14) ( 129 + 71) * 72 = 14400 |
| 15) | 61 * 42 + 158 * 61 = | | 15) ( 158 + 42) * 61 = 12200 |
| 16) | 143 * 45 + 45 * 57 = | | 16) ( 143 + 57) * 45 = 9000 |
| 17) | 59 * 42 + 42 * 141 = | | 17) ( 141 + 59) * 42 = 8400 |
| 18) | 158 * 47 - 58 * 47 = | | 18) ( 158 - 58) * 47 = 4700 |
| 19) | 81 * 159 + 41 * 81 = | | 19) ( 159 + 41) * 81 = 16200 |
| 20) | 75 * 91 + 91 * 125 = | | 20) ( 125 + 75) * 91 = 18200 |
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Score: ______________ | |
