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 25 2026
08:09:43 PM | Monday May 25 2026
08:09:43 PMFlip Answers |
| 1) | 203 * 197 = | | 1) 200 * 200 - 3 * 3 = 39991 |
| 2) | 97 * 103 = | | 2) 100 * 100 - 3 * 3 = 9991 |
| 3) | 307 * 293 = | | 3) 300 * 300 - 7 * 7 = 89951 |
| 4) | 292 * 308 = | | 4) 300 * 300 - 8 * 8 = 89936 |
| 5) | 393 * 407 = | | 5) 400 * 400 - 7 * 7 = 159951 |
| 6) | 95 * 105 = | | 6) 100 * 100 - 5 * 5 = 9975 |
| 7) | 309 * 291 = | | 7) 300 * 300 - 9 * 9 = 89919 |
| 8) | 101 * 99 = | | 8) 100 * 100 - 1 * 1 = 9999 |
| 9) | 204 * 196 = | | 9) 200 * 200 - 4 * 4 = 39984 |
| 10) | 202 * 198 = | | 10) 200 * 200 - 2 * 2 = 39996 |
| 11) | 130 * 93 + 93 * 70 = | | 11) ( 130 + 70) * 93 = 18600 |
| 12) | 245 * 75 - 45 * 75 = | | 12) ( 245 - 45) * 75 = 15000 |
| 13) | 22 * 55 + 45 * 22 = | | 13) ( 45 + 55) * 22 = 2200 |
| 14) | 31 * 237 - 31 * 37 = | | 14) ( 237 - 37) * 31 = 6200 |
| 15) | 36 * 47 + 64 * 47 = | | 15) ( 64 + 36) * 47 = 4700 |
| 16) | 249 * 87 - 87 * 49 = | | 16) ( 249 - 49) * 87 = 17400 |
| 17) | 77 * 127 + 73 * 77 = | | 17) ( 127 + 73) * 77 = 15400 |
| 18) | 62 * 273 - 73 * 62 = | | 18) ( 273 - 73) * 62 = 12400 |
| 19) | 44 * 57 + 143 * 44 = | | 19) ( 143 + 57) * 44 = 8800 |
| 20) | 25 * 46 + 46 * 75 = | | 20) ( 25 + 75) * 46 = 4600 |
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Score: ______________ | |
