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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Saturday April 18 2026
10:17:48 AM | Saturday April 18 2026
10:17:48 AMFlip Answers |
| 1) | 301 * 299 = | | 1) 300 * 300 - 1 * 1 = 89999 |
| 2) | 96 * 104 = | | 2) 100 * 100 - 4 * 4 = 9984 |
| 3) | 99 * 101 = | | 3) 100 * 100 - 1 * 1 = 9999 |
| 4) | 399 * 401 = | | 4) 400 * 400 - 1 * 1 = 159999 |
| 5) | 408 * 392 = | | 5) 400 * 400 - 8 * 8 = 159936 |
| 6) | 295 * 305 = | | 6) 300 * 300 - 5 * 5 = 89975 |
| 7) | 91 * 109 = | | 7) 100 * 100 - 9 * 9 = 9919 |
| 8) | 407 * 393 = | | 8) 400 * 400 - 7 * 7 = 159951 |
| 9) | 97 * 103 = | | 9) 100 * 100 - 3 * 3 = 9991 |
| 10) | 101 * 99 = | | 10) 100 * 100 - 1 * 1 = 9999 |
| 11) | 30 * 35 + 65 * 30 = | | 11) ( 35 + 65) * 30 = 3000 |
| 12) | 167 * 50 - 67 * 50 = | | 12) ( 167 - 67) * 50 = 5000 |
| 13) | 161 * 24 - 61 * 24 = | | 13) ( 161 - 61) * 24 = 2400 |
| 14) | 45 * 87 + 155 * 87 = | | 14) ( 155 + 45) * 87 = 17400 |
| 15) | 252 * 52 - 52 * 52 = | | 15) ( 252 - 52) * 52 = 10400 |
| 16) | 251 * 28 - 51 * 28 = | | 16) ( 251 - 51) * 28 = 5600 |
| 17) | 272 * 71 - 72 * 71 = | | 17) ( 272 - 72) * 71 = 14200 |
| 18) | 150 * 85 + 50 * 85 = | | 18) ( 150 + 50) * 85 = 17000 |
| 19) | 79 * 39 + 79 * 161 = | | 19) ( 161 + 39) * 79 = 15800 |
| 20) | 140 * 42 - 40 * 42 = | | 20) ( 140 - 40) * 42 = 4200 |
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Score: ______________ | |
