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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Sunday October 25 2026
06:27:47 AM | Sunday October 25 2026
06:27:47 AMFlip Answers |
| 1) | 406 * 394 = | | 1) 400 * 400 - 6 * 6 = 159964 |
| 2) | 207 * 193 = | | 2) 200 * 200 - 7 * 7 = 39951 |
| 3) | 105 * 95 = | | 3) 100 * 100 - 5 * 5 = 9975 |
| 4) | 104 * 96 = | | 4) 100 * 100 - 4 * 4 = 9984 |
| 5) | 92 * 108 = | | 5) 100 * 100 - 8 * 8 = 9936 |
| 6) | 399 * 401 = | | 6) 400 * 400 - 1 * 1 = 159999 |
| 7) | 96 * 104 = | | 7) 100 * 100 - 4 * 4 = 9984 |
| 8) | 96 * 104 = | | 8) 100 * 100 - 4 * 4 = 9984 |
| 9) | 395 * 405 = | | 9) 400 * 400 - 5 * 5 = 159975 |
| 10) | 203 * 197 = | | 10) 200 * 200 - 3 * 3 = 39991 |
| 11) | 21 * 272 - 21 * 72 = | | 11) ( 272 - 72) * 21 = 4200 |
| 12) | 251 * 69 - 69 * 51 = | | 12) ( 251 - 51) * 69 = 13800 |
| 13) | 96 * 242 - 96 * 42 = | | 13) ( 242 - 42) * 96 = 19200 |
| 14) | 36 * 28 + 36 * 72 = | | 14) ( 28 + 72) * 36 = 3600 |
| 15) | 248 * 36 - 36 * 48 = | | 15) ( 248 - 48) * 36 = 7200 |
| 16) | 91 * 143 - 43 * 91 = | | 16) ( 143 - 43) * 91 = 9100 |
| 17) | 28 * 139 - 39 * 28 = | | 17) ( 139 - 39) * 28 = 2800 |
| 18) | 40 * 46 + 54 * 40 = | | 18) ( 54 + 46) * 40 = 4000 |
| 19) | 53 * 258 - 58 * 53 = | | 19) ( 258 - 58) * 53 = 10600 |
| 20) | 51 * 37 + 37 * 149 = | | 20) ( 149 + 51) * 37 = 7400 |
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Score: ______________ | |
