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 April 15 2026
07:50:51 PM | Wednesday April 15 2026
07:50:51 PMFlip Answers |
| 1) | 307 * 293 = | | 1) 300 * 300 - 7 * 7 = 89951 |
| 2) | 107 * 93 = | | 2) 100 * 100 - 7 * 7 = 9951 |
| 3) | 405 * 395 = | | 3) 400 * 400 - 5 * 5 = 159975 |
| 4) | 296 * 304 = | | 4) 300 * 300 - 4 * 4 = 89984 |
| 5) | 190 * 210 = | | 5) 200 * 200 - 10 * 10 = 39900 |
| 6) | 396 * 404 = | | 6) 400 * 400 - 4 * 4 = 159984 |
| 7) | 302 * 298 = | | 7) 300 * 300 - 2 * 2 = 89996 |
| 8) | 410 * 390 = | | 8) 400 * 400 - 10 * 10 = 159900 |
| 9) | 104 * 96 = | | 9) 100 * 100 - 4 * 4 = 9984 |
| 10) | 97 * 103 = | | 10) 100 * 100 - 3 * 3 = 9991 |
| 11) | 41 * 259 - 59 * 41 = | | 11) ( 259 - 59) * 41 = 8200 |
| 12) | 23 * 258 - 58 * 23 = | | 12) ( 258 - 58) * 23 = 4600 |
| 13) | 68 * 97 + 32 * 97 = | | 13) ( 32 + 68) * 97 = 9700 |
| 14) | 252 * 67 - 67 * 52 = | | 14) ( 252 - 52) * 67 = 13400 |
| 15) | 272 * 69 - 72 * 69 = | | 15) ( 272 - 72) * 69 = 13800 |
| 16) | 71 * 89 + 129 * 89 = | | 16) ( 129 + 71) * 89 = 17800 |
| 17) | 143 * 68 - 68 * 43 = | | 17) ( 143 - 43) * 68 = 6800 |
| 18) | 260 * 47 - 60 * 47 = | | 18) ( 260 - 60) * 47 = 9400 |
| 19) | 70 * 74 + 74 * 30 = | | 19) ( 30 + 70) * 74 = 7400 |
| 20) | 61 * 55 + 55 * 139 = | | 20) ( 139 + 61) * 55 = 11000 |
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Score: ______________ | |
