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 March 31 2025
05:57:42 AM | Monday March 31 2025
05:57:42 AMFlip Answers |
| 1) | 397 * 403 = | | 1) 400 * 400 - 3 * 3 = 159991 |
| 2) | 304 * 296 = | | 2) 300 * 300 - 4 * 4 = 89984 |
| 3) | 305 * 295 = | | 3) 300 * 300 - 5 * 5 = 89975 |
| 4) | 95 * 105 = | | 4) 100 * 100 - 5 * 5 = 9975 |
| 5) | 205 * 195 = | | 5) 200 * 200 - 5 * 5 = 39975 |
| 6) | 203 * 197 = | | 6) 200 * 200 - 3 * 3 = 39991 |
| 7) | 199 * 201 = | | 7) 200 * 200 - 1 * 1 = 39999 |
| 8) | 409 * 391 = | | 8) 400 * 400 - 9 * 9 = 159919 |
| 9) | 391 * 409 = | | 9) 400 * 400 - 9 * 9 = 159919 |
| 10) | 197 * 203 = | | 10) 200 * 200 - 3 * 3 = 39991 |
| 11) | 41 * 54 + 54 * 159 = | | 11) ( 159 + 41) * 54 = 10800 |
| 12) | 259 * 79 - 59 * 79 = | | 12) ( 259 - 59) * 79 = 15800 |
| 13) | 30 * 52 + 48 * 30 = | | 13) ( 48 + 52) * 30 = 3000 |
| 14) | 133 * 39 + 39 * 67 = | | 14) ( 133 + 67) * 39 = 7800 |
| 15) | 22 * 248 - 48 * 22 = | | 15) ( 248 - 48) * 22 = 4400 |
| 16) | 62 * 152 - 62 * 52 = | | 16) ( 152 - 52) * 62 = 6200 |
| 17) | 40 * 254 - 40 * 54 = | | 17) ( 254 - 54) * 40 = 8000 |
| 18) | 157 * 90 - 57 * 90 = | | 18) ( 157 - 57) * 90 = 9000 |
| 19) | 68 * 71 + 129 * 68 = | | 19) ( 129 + 71) * 68 = 13600 |
| 20) | 50 * 40 + 50 * 160 = | | 20) ( 160 + 40) * 50 = 10000 |
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Score: ______________ | |
