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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Monday October 20 2025
03:10:56 AM | Monday October 20 2025
03:10:56 AMFlip Answers |
| 1) | 199 * 201 = | | 1) 200 * 200 - 1 * 1 = 39999 |
| 2) | 306 * 294 = | | 2) 300 * 300 - 6 * 6 = 89964 |
| 3) | 198 * 202 = | | 3) 200 * 200 - 2 * 2 = 39996 |
| 4) | 195 * 205 = | | 4) 200 * 200 - 5 * 5 = 39975 |
| 5) | 91 * 109 = | | 5) 100 * 100 - 9 * 9 = 9919 |
| 6) | 309 * 291 = | | 6) 300 * 300 - 9 * 9 = 89919 |
| 7) | 207 * 193 = | | 7) 200 * 200 - 7 * 7 = 39951 |
| 8) | 95 * 105 = | | 8) 100 * 100 - 5 * 5 = 9975 |
| 9) | 105 * 95 = | | 9) 100 * 100 - 5 * 5 = 9975 |
| 10) | 397 * 403 = | | 10) 400 * 400 - 3 * 3 = 159991 |
| 11) | 57 * 28 + 28 * 43 = | | 11) ( 43 + 57) * 28 = 2800 |
| 12) | 139 * 26 - 39 * 26 = | | 12) ( 139 - 39) * 26 = 2600 |
| 13) | 236 * 51 - 51 * 36 = | | 13) ( 236 - 36) * 51 = 10200 |
| 14) | 71 * 56 + 56 * 129 = | | 14) ( 129 + 71) * 56 = 11200 |
| 15) | 84 * 50 + 84 * 50 = | | 15) ( 50 + 50) * 84 = 8400 |
| 16) | 151 * 59 - 59 * 51 = | | 16) ( 151 - 51) * 59 = 5900 |
| 17) | 155 * 83 - 55 * 83 = | | 17) ( 155 - 55) * 83 = 8300 |
| 18) | 241 * 78 - 41 * 78 = | | 18) ( 241 - 41) * 78 = 15600 |
| 19) | 81 * 166 - 81 * 66 = | | 19) ( 166 - 66) * 81 = 8100 |
| 20) | 25 * 87 + 87 * 75 = | | 20) ( 25 + 75) * 87 = 8700 |
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Score: ______________ | |
