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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Tuesday March 10 2026 09:48:12 AM | Tuesday March 10 2026 09:48:12 AMFlip Answers |
| 1) | 310 * 290 = | | 1) 300 * 300 - 10 * 10 = 89900 |
| 2) | 202 * 198 = | | 2) 200 * 200 - 2 * 2 = 39996 |
| 3) | 292 * 308 = | | 3) 300 * 300 - 8 * 8 = 89936 |
| 4) | 207 * 193 = | | 4) 200 * 200 - 7 * 7 = 39951 |
| 5) | 399 * 401 = | | 5) 400 * 400 - 1 * 1 = 159999 |
| 6) | 110 * 90 = | | 6) 100 * 100 - 10 * 10 = 9900 |
| 7) | 96 * 104 = | | 7) 100 * 100 - 4 * 4 = 9984 |
| 8) | 101 * 99 = | | 8) 100 * 100 - 1 * 1 = 9999 |
| 9) | 310 * 290 = | | 9) 300 * 300 - 10 * 10 = 89900 |
| 10) | 210 * 190 = | | 10) 200 * 200 - 10 * 10 = 39900 |
| 11) | 151 * 44 - 51 * 44 = | | 11) ( 151 - 51) * 44 = 4400 |
| 12) | 47 * 258 - 47 * 58 = | | 12) ( 258 - 58) * 47 = 9400 |
| 13) | 73 * 263 - 73 * 63 = | | 13) ( 263 - 63) * 73 = 14600 |
| 14) | 53 * 23 + 23 * 47 = | | 14) ( 47 + 53) * 23 = 2300 |
| 15) | 167 * 42 - 67 * 42 = | | 15) ( 167 - 67) * 42 = 4200 |
| 16) | 67 * 83 + 83 * 33 = | | 16) ( 33 + 67) * 83 = 8300 |
| 17) | 76 * 138 + 62 * 76 = | | 17) ( 138 + 62) * 76 = 15200 |
| 18) | 58 * 125 + 75 * 58 = | | 18) ( 125 + 75) * 58 = 11600 |
| 19) | 64 * 155 + 64 * 45 = | | 19) ( 155 + 45) * 64 = 12800 |
| 20) | 24 * 42 + 24 * 158 = | | 20) ( 158 + 42) * 24 = 4800 |
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Score: ______________ | |