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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Wednesday October 14 2026
07:27:30 PM | Wednesday October 14 2026
07:27:30 PMFlip Answers |
| 1) | 397 * 403 = | | 1) 400 * 400 - 3 * 3 = 159991 |
| 2) | 294 * 306 = | | 2) 300 * 300 - 6 * 6 = 89964 |
| 3) | 109 * 91 = | | 3) 100 * 100 - 9 * 9 = 9919 |
| 4) | 203 * 197 = | | 4) 200 * 200 - 3 * 3 = 39991 |
| 5) | 402 * 398 = | | 5) 400 * 400 - 2 * 2 = 159996 |
| 6) | 197 * 203 = | | 6) 200 * 200 - 3 * 3 = 39991 |
| 7) | 199 * 201 = | | 7) 200 * 200 - 1 * 1 = 39999 |
| 8) | 109 * 91 = | | 8) 100 * 100 - 9 * 9 = 9919 |
| 9) | 206 * 194 = | | 9) 200 * 200 - 6 * 6 = 39964 |
| 10) | 395 * 405 = | | 10) 400 * 400 - 5 * 5 = 159975 |
| 11) | 53 * 166 - 66 * 53 = | | 11) ( 166 - 66) * 53 = 5300 |
| 12) | 40 * 154 - 40 * 54 = | | 12) ( 154 - 54) * 40 = 4000 |
| 13) | 144 * 69 + 69 * 56 = | | 13) ( 144 + 56) * 69 = 13800 |
| 14) | 58 * 93 + 93 * 42 = | | 14) ( 42 + 58) * 93 = 9300 |
| 15) | 268 * 41 - 41 * 68 = | | 15) ( 268 - 68) * 41 = 8200 |
| 16) | 66 * 152 + 66 * 48 = | | 16) ( 152 + 48) * 66 = 13200 |
| 17) | 168 * 97 - 97 * 68 = | | 17) ( 168 - 68) * 97 = 9700 |
| 18) | 65 * 165 - 65 * 65 = | | 18) ( 165 - 65) * 65 = 6500 |
| 19) | 44 * 92 + 92 * 156 = | | 19) ( 156 + 44) * 92 = 18400 |
| 20) | 72 * 137 - 72 * 37 = | | 20) ( 137 - 37) * 72 = 7200 |
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Score: ______________ | |
