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 May 11 2026 01:04:08 PM | Monday May 11 2026 01:04:08 PMFlip Answers |
| 1) | 207 * 193 = | | 1) 200 * 200 - 7 * 7 = 39951 |
| 2) | 202 * 198 = | | 2) 200 * 200 - 2 * 2 = 39996 |
| 3) | 391 * 409 = | | 3) 400 * 400 - 9 * 9 = 159919 |
| 4) | 106 * 94 = | | 4) 100 * 100 - 6 * 6 = 9964 |
| 5) | 397 * 403 = | | 5) 400 * 400 - 3 * 3 = 159991 |
| 6) | 99 * 101 = | | 6) 100 * 100 - 1 * 1 = 9999 |
| 7) | 203 * 197 = | | 7) 200 * 200 - 3 * 3 = 39991 |
| 8) | 306 * 294 = | | 8) 300 * 300 - 6 * 6 = 89964 |
| 9) | 108 * 92 = | | 9) 100 * 100 - 8 * 8 = 9936 |
| 10) | 307 * 293 = | | 10) 300 * 300 - 7 * 7 = 89951 |
| 11) | 238 * 72 - 72 * 38 = | | 11) ( 238 - 38) * 72 = 14400 |
| 12) | 152 * 23 - 23 * 52 = | | 12) ( 152 - 52) * 23 = 2300 |
| 13) | 149 * 66 - 66 * 49 = | | 13) ( 149 - 49) * 66 = 6600 |
| 14) | 23 * 50 + 50 * 23 = | | 14) ( 50 + 50) * 23 = 2300 |
| 15) | 149 * 33 - 33 * 49 = | | 15) ( 149 - 49) * 33 = 3300 |
| 16) | 39 * 271 - 39 * 71 = | | 16) ( 271 - 71) * 39 = 7800 |
| 17) | 94 * 64 + 36 * 94 = | | 17) ( 64 + 36) * 94 = 9400 |
| 18) | 60 * 57 + 57 * 140 = | | 18) ( 140 + 60) * 57 = 11400 |
| 19) | 73 * 48 + 52 * 73 = | | 19) ( 52 + 48) * 73 = 7300 |
| 20) | 259 * 90 - 59 * 90 = | | 20) ( 259 - 59) * 90 = 18000 |
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Score: ______________ | |