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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Thursday February 05 2026
05:18:50 AM | Thursday February 05 2026
05:18:50 AMFlip Answers |
| 1) | 291 * 309 = | | 1) 300 * 300 - 9 * 9 = 89919 |
| 2) | 195 * 205 = | | 2) 200 * 200 - 5 * 5 = 39975 |
| 3) | 310 * 290 = | | 3) 300 * 300 - 10 * 10 = 89900 |
| 4) | 309 * 291 = | | 4) 300 * 300 - 9 * 9 = 89919 |
| 5) | 294 * 306 = | | 5) 300 * 300 - 6 * 6 = 89964 |
| 6) | 101 * 99 = | | 6) 100 * 100 - 1 * 1 = 9999 |
| 7) | 197 * 203 = | | 7) 200 * 200 - 3 * 3 = 39991 |
| 8) | 208 * 192 = | | 8) 200 * 200 - 8 * 8 = 39936 |
| 9) | 395 * 405 = | | 9) 400 * 400 - 5 * 5 = 159975 |
| 10) | 310 * 290 = | | 10) 300 * 300 - 10 * 10 = 89900 |
| 11) | 29 * 68 + 68 * 71 = | | 11) ( 29 + 71) * 68 = 6800 |
| 12) | 42 * 71 + 42 * 129 = | | 12) ( 129 + 71) * 42 = 8400 |
| 13) | 42 * 39 + 39 * 58 = | | 13) ( 42 + 58) * 39 = 3900 |
| 14) | 81 * 261 - 81 * 61 = | | 14) ( 261 - 61) * 81 = 16200 |
| 15) | 80 * 262 - 62 * 80 = | | 15) ( 262 - 62) * 80 = 16000 |
| 16) | 57 * 67 + 67 * 43 = | | 16) ( 57 + 43) * 67 = 6700 |
| 17) | 69 * 149 + 51 * 69 = | | 17) ( 149 + 51) * 69 = 13800 |
| 18) | 74 * 58 + 58 * 126 = | | 18) ( 126 + 74) * 58 = 11600 |
| 19) | 39 * 80 + 80 * 61 = | | 19) ( 39 + 61) * 80 = 8000 |
| 20) | 34 * 85 + 85 * 66 = | | 20) ( 34 + 66) * 85 = 8500 |
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Score: ______________ | |
