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 10 2025
02:21:44 PM | Wednesday December 10 2025
02:21:44 PMFlip Answers |
| 1) | 404 * 396 = | | 1) 400 * 400 - 4 * 4 = 159984 |
| 2) | 202 * 198 = | | 2) 200 * 200 - 2 * 2 = 39996 |
| 3) | 103 * 97 = | | 3) 100 * 100 - 3 * 3 = 9991 |
| 4) | 204 * 196 = | | 4) 200 * 200 - 4 * 4 = 39984 |
| 5) | 199 * 201 = | | 5) 200 * 200 - 1 * 1 = 39999 |
| 6) | 92 * 108 = | | 6) 100 * 100 - 8 * 8 = 9936 |
| 7) | 390 * 410 = | | 7) 400 * 400 - 10 * 10 = 159900 |
| 8) | 303 * 297 = | | 8) 300 * 300 - 3 * 3 = 89991 |
| 9) | 393 * 407 = | | 9) 400 * 400 - 7 * 7 = 159951 |
| 10) | 102 * 98 = | | 10) 100 * 100 - 2 * 2 = 9996 |
| 11) | 268 * 93 - 68 * 93 = | | 11) ( 268 - 68) * 93 = 18600 |
| 12) | 58 * 159 - 59 * 58 = | | 12) ( 159 - 59) * 58 = 5800 |
| 13) | 50 * 92 + 92 * 50 = | | 13) ( 50 + 50) * 92 = 9200 |
| 14) | 53 * 70 + 53 * 30 = | | 14) ( 30 + 70) * 53 = 5300 |
| 15) | 90 * 165 - 65 * 90 = | | 15) ( 165 - 65) * 90 = 9000 |
| 16) | 174 * 37 - 74 * 37 = | | 16) ( 174 - 74) * 37 = 3700 |
| 17) | 142 * 55 + 58 * 55 = | | 17) ( 142 + 58) * 55 = 11000 |
| 18) | 86 * 61 + 139 * 86 = | | 18) ( 139 + 61) * 86 = 17200 |
| 19) | 134 * 83 + 66 * 83 = | | 19) ( 134 + 66) * 83 = 16600 |
| 20) | 41 * 249 - 41 * 49 = | | 20) ( 249 - 49) * 41 = 8200 |
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Score: ______________ | |
