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 June 21 2026 03:53:07 AM | Sunday June 21 2026 03:53:07 AMFlip Answers |
| 1) | 407 * 393 = | | 1) 400 * 400 - 7 * 7 = 159951 |
| 2) | 292 * 308 = | | 2) 300 * 300 - 8 * 8 = 89936 |
| 3) | 207 * 193 = | | 3) 200 * 200 - 7 * 7 = 39951 |
| 4) | 194 * 206 = | | 4) 200 * 200 - 6 * 6 = 39964 |
| 5) | 195 * 205 = | | 5) 200 * 200 - 5 * 5 = 39975 |
| 6) | 103 * 97 = | | 6) 100 * 100 - 3 * 3 = 9991 |
| 7) | 303 * 297 = | | 7) 300 * 300 - 3 * 3 = 89991 |
| 8) | 298 * 302 = | | 8) 300 * 300 - 2 * 2 = 89996 |
| 9) | 97 * 103 = | | 9) 100 * 100 - 3 * 3 = 9991 |
| 10) | 397 * 403 = | | 10) 400 * 400 - 3 * 3 = 159991 |
| 11) | 30 * 155 - 30 * 55 = | | 11) ( 155 - 55) * 30 = 3000 |
| 12) | 92 * 167 - 67 * 92 = | | 12) ( 167 - 67) * 92 = 9200 |
| 13) | 38 * 46 + 62 * 46 = | | 13) ( 62 + 38) * 46 = 4600 |
| 14) | 258 * 35 - 58 * 35 = | | 14) ( 258 - 58) * 35 = 7000 |
| 15) | 61 * 82 + 39 * 82 = | | 15) ( 61 + 39) * 82 = 8200 |
| 16) | 24 * 50 + 24 * 50 = | | 16) ( 50 + 50) * 24 = 2400 |
| 17) | 175 * 79 - 79 * 75 = | | 17) ( 175 - 75) * 79 = 7900 |
| 18) | 62 * 72 + 72 * 138 = | | 18) ( 138 + 62) * 72 = 14400 |
| 19) | 73 * 73 + 27 * 73 = | | 19) ( 27 + 73) * 73 = 7300 |
| 20) | 60 * 31 + 40 * 31 = | | 20) ( 40 + 60) * 31 = 3100 |
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Score: ______________ | |