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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Friday October 10 2025
11:07:56 AM | Friday October 10 2025
11:07:56 AMFlip Answers |
| 1) | 403 * 397 = | | 1) 400 * 400 - 3 * 3 = 159991 |
| 2) | 307 * 293 = | | 2) 300 * 300 - 7 * 7 = 89951 |
| 3) | 396 * 404 = | | 3) 400 * 400 - 4 * 4 = 159984 |
| 4) | 106 * 94 = | | 4) 100 * 100 - 6 * 6 = 9964 |
| 5) | 96 * 104 = | | 5) 100 * 100 - 4 * 4 = 9984 |
| 6) | 102 * 98 = | | 6) 100 * 100 - 2 * 2 = 9996 |
| 7) | 210 * 190 = | | 7) 200 * 200 - 10 * 10 = 39900 |
| 8) | 398 * 402 = | | 8) 400 * 400 - 2 * 2 = 159996 |
| 9) | 193 * 207 = | | 9) 200 * 200 - 7 * 7 = 39951 |
| 10) | 197 * 203 = | | 10) 200 * 200 - 3 * 3 = 39991 |
| 11) | 50 * 51 + 50 * 49 = | | 11) ( 49 + 51) * 50 = 5000 |
| 12) | 272 * 85 - 72 * 85 = | | 12) ( 272 - 72) * 85 = 17000 |
| 13) | 91 * 50 + 150 * 91 = | | 13) ( 150 + 50) * 91 = 18200 |
| 14) | 50 * 174 - 50 * 74 = | | 14) ( 174 - 74) * 50 = 5000 |
| 15) | 56 * 84 + 84 * 44 = | | 15) ( 44 + 56) * 84 = 8400 |
| 16) | 89 * 47 + 89 * 153 = | | 16) ( 153 + 47) * 89 = 17800 |
| 17) | 240 * 50 - 40 * 50 = | | 17) ( 240 - 40) * 50 = 10000 |
| 18) | 61 * 68 + 132 * 61 = | | 18) ( 132 + 68) * 61 = 12200 |
| 19) | 92 * 146 - 46 * 92 = | | 19) ( 146 - 46) * 92 = 9200 |
| 20) | 50 * 48 + 48 * 150 = | | 20) ( 150 + 50) * 48 = 9600 |
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Score: ______________ | |
