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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Friday June 26 2026
02:15:15 PM | Friday June 26 2026
02:15:15 PMFlip Answers |
| 1) | 193 * 207 = | | 1) 200 * 200 - 7 * 7 = 39951 |
| 2) | 91 * 109 = | | 2) 100 * 100 - 9 * 9 = 9919 |
| 3) | 93 * 107 = | | 3) 100 * 100 - 7 * 7 = 9951 |
| 4) | 406 * 394 = | | 4) 400 * 400 - 6 * 6 = 159964 |
| 5) | 99 * 101 = | | 5) 100 * 100 - 1 * 1 = 9999 |
| 6) | 297 * 303 = | | 6) 300 * 300 - 3 * 3 = 89991 |
| 7) | 309 * 291 = | | 7) 300 * 300 - 9 * 9 = 89919 |
| 8) | 393 * 407 = | | 8) 400 * 400 - 7 * 7 = 159951 |
| 9) | 295 * 305 = | | 9) 300 * 300 - 5 * 5 = 89975 |
| 10) | 204 * 196 = | | 10) 200 * 200 - 4 * 4 = 39984 |
| 11) | 46 * 75 + 75 * 54 = | | 11) ( 54 + 46) * 75 = 7500 |
| 12) | 46 * 94 + 54 * 94 = | | 12) ( 46 + 54) * 94 = 9400 |
| 13) | 54 * 65 + 65 * 146 = | | 13) ( 146 + 54) * 65 = 13000 |
| 14) | 70 * 31 + 69 * 70 = | | 14) ( 31 + 69) * 70 = 7000 |
| 15) | 129 * 85 + 71 * 85 = | | 15) ( 129 + 71) * 85 = 17000 |
| 16) | 141 * 36 - 41 * 36 = | | 16) ( 141 - 41) * 36 = 3600 |
| 17) | 26 * 25 + 25 * 74 = | | 17) ( 26 + 74) * 25 = 2500 |
| 18) | 240 * 82 - 40 * 82 = | | 18) ( 240 - 40) * 82 = 16400 |
| 19) | 267 * 31 - 31 * 67 = | | 19) ( 267 - 67) * 31 = 6200 |
| 20) | 96 * 170 - 96 * 70 = | | 20) ( 170 - 70) * 96 = 9600 |
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Score: ______________ | |
