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 July 13 2026
06:07:05 AM | Monday July 13 2026
06:07:05 AMFlip Answers |
| 1) | 401 * 399 = | | 1) 400 * 400 - 1 * 1 = 159999 |
| 2) | 97 * 103 = | | 2) 100 * 100 - 3 * 3 = 9991 |
| 3) | 295 * 305 = | | 3) 300 * 300 - 5 * 5 = 89975 |
| 4) | 398 * 402 = | | 4) 400 * 400 - 2 * 2 = 159996 |
| 5) | 104 * 96 = | | 5) 100 * 100 - 4 * 4 = 9984 |
| 6) | 110 * 90 = | | 6) 100 * 100 - 10 * 10 = 9900 |
| 7) | 202 * 198 = | | 7) 200 * 200 - 2 * 2 = 39996 |
| 8) | 97 * 103 = | | 8) 100 * 100 - 3 * 3 = 9991 |
| 9) | 92 * 108 = | | 9) 100 * 100 - 8 * 8 = 9936 |
| 10) | 197 * 203 = | | 10) 200 * 200 - 3 * 3 = 39991 |
| 11) | 175 * 63 - 75 * 63 = | | 11) ( 175 - 75) * 63 = 6300 |
| 12) | 65 * 161 - 61 * 65 = | | 12) ( 161 - 61) * 65 = 6500 |
| 13) | 38 * 38 + 62 * 38 = | | 13) ( 38 + 62) * 38 = 3800 |
| 14) | 39 * 72 + 61 * 72 = | | 14) ( 61 + 39) * 72 = 7200 |
| 15) | 69 * 70 + 69 * 30 = | | 15) ( 30 + 70) * 69 = 6900 |
| 16) | 92 * 42 + 58 * 92 = | | 16) ( 42 + 58) * 92 = 9200 |
| 17) | 49 * 261 - 49 * 61 = | | 17) ( 261 - 61) * 49 = 9800 |
| 18) | 26 * 49 + 26 * 51 = | | 18) ( 49 + 51) * 26 = 2600 |
| 19) | 248 * 55 - 48 * 55 = | | 19) ( 248 - 48) * 55 = 11000 |
| 20) | 82 * 135 - 35 * 82 = | | 20) ( 135 - 35) * 82 = 8200 |
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Score: ______________ | |
