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 June 15 2026
03:19:50 AM | Monday June 15 2026
03:19:50 AMFlip Answers |
| 1) | 195 * 205 = | | 1) 200 * 200 - 5 * 5 = 39975 |
| 2) | 399 * 401 = | | 2) 400 * 400 - 1 * 1 = 159999 |
| 3) | 401 * 399 = | | 3) 400 * 400 - 1 * 1 = 159999 |
| 4) | 98 * 102 = | | 4) 100 * 100 - 2 * 2 = 9996 |
| 5) | 95 * 105 = | | 5) 100 * 100 - 5 * 5 = 9975 |
| 6) | 308 * 292 = | | 6) 300 * 300 - 8 * 8 = 89936 |
| 7) | 293 * 307 = | | 7) 300 * 300 - 7 * 7 = 89951 |
| 8) | 95 * 105 = | | 8) 100 * 100 - 5 * 5 = 9975 |
| 9) | 90 * 110 = | | 9) 100 * 100 - 10 * 10 = 9900 |
| 10) | 198 * 202 = | | 10) 200 * 200 - 2 * 2 = 39996 |
| 11) | 49 * 68 + 68 * 51 = | | 11) ( 49 + 51) * 68 = 6800 |
| 12) | 46 * 75 + 46 * 25 = | | 12) ( 25 + 75) * 46 = 4600 |
| 13) | 45 * 79 + 155 * 79 = | | 13) ( 155 + 45) * 79 = 15800 |
| 14) | 42 * 172 - 42 * 72 = | | 14) ( 172 - 72) * 42 = 4200 |
| 15) | 154 * 83 - 54 * 83 = | | 15) ( 154 - 54) * 83 = 8300 |
| 16) | 94 * 139 + 94 * 61 = | | 16) ( 139 + 61) * 94 = 18800 |
| 17) | 38 * 91 + 91 * 62 = | | 17) ( 62 + 38) * 91 = 9100 |
| 18) | 173 * 35 - 35 * 73 = | | 18) ( 173 - 73) * 35 = 3500 |
| 19) | 82 * 47 + 82 * 53 = | | 19) ( 47 + 53) * 82 = 8200 |
| 20) | 45 * 66 + 155 * 66 = | | 20) ( 155 + 45) * 66 = 13200 |
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Score: ______________ | |
