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 September 28 2026
04:48:46 AM | Monday September 28 2026
04:48:46 AMFlip Answers |
| 1) | 193 * 207 = | | 1) 200 * 200 - 7 * 7 = 39951 |
| 2) | 209 * 191 = | | 2) 200 * 200 - 9 * 9 = 39919 |
| 3) | 199 * 201 = | | 3) 200 * 200 - 1 * 1 = 39999 |
| 4) | 103 * 97 = | | 4) 100 * 100 - 3 * 3 = 9991 |
| 5) | 395 * 405 = | | 5) 400 * 400 - 5 * 5 = 159975 |
| 6) | 207 * 193 = | | 6) 200 * 200 - 7 * 7 = 39951 |
| 7) | 406 * 394 = | | 7) 400 * 400 - 6 * 6 = 159964 |
| 8) | 205 * 195 = | | 8) 200 * 200 - 5 * 5 = 39975 |
| 9) | 404 * 396 = | | 9) 400 * 400 - 4 * 4 = 159984 |
| 10) | 410 * 390 = | | 10) 400 * 400 - 10 * 10 = 159900 |
| 11) | 56 * 158 - 56 * 58 = | | 11) ( 158 - 58) * 56 = 5600 |
| 12) | 85 * 243 - 43 * 85 = | | 12) ( 243 - 43) * 85 = 17000 |
| 13) | 62 * 170 - 62 * 70 = | | 13) ( 170 - 70) * 62 = 6200 |
| 14) | 152 * 91 - 52 * 91 = | | 14) ( 152 - 52) * 91 = 9100 |
| 15) | 32 * 35 + 165 * 32 = | | 15) ( 165 + 35) * 32 = 6400 |
| 16) | 37 * 44 + 37 * 56 = | | 16) ( 44 + 56) * 37 = 3700 |
| 17) | 138 * 41 - 41 * 38 = | | 17) ( 138 - 38) * 41 = 4100 |
| 18) | 41 * 258 - 58 * 41 = | | 18) ( 258 - 58) * 41 = 8200 |
| 19) | 90 * 158 + 42 * 90 = | | 19) ( 158 + 42) * 90 = 18000 |
| 20) | 95 * 150 - 95 * 50 = | | 20) ( 150 - 50) * 95 = 9500 |
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Score: ______________ | |
