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 November 09 2026
01:15:38 PM | Monday November 09 2026
01:15:38 PMFlip Answers |
| 1) | 407 * 393 = | | 1) 400 * 400 - 7 * 7 = 159951 |
| 2) | 393 * 407 = | | 2) 400 * 400 - 7 * 7 = 159951 |
| 3) | 294 * 306 = | | 3) 300 * 300 - 6 * 6 = 89964 |
| 4) | 210 * 190 = | | 4) 200 * 200 - 10 * 10 = 39900 |
| 5) | 295 * 305 = | | 5) 300 * 300 - 5 * 5 = 89975 |
| 6) | 206 * 194 = | | 6) 200 * 200 - 6 * 6 = 39964 |
| 7) | 396 * 404 = | | 7) 400 * 400 - 4 * 4 = 159984 |
| 8) | 197 * 203 = | | 8) 200 * 200 - 3 * 3 = 39991 |
| 9) | 408 * 392 = | | 9) 400 * 400 - 8 * 8 = 159936 |
| 10) | 103 * 97 = | | 10) 100 * 100 - 3 * 3 = 9991 |
| 11) | 154 * 52 + 46 * 52 = | | 11) ( 154 + 46) * 52 = 10400 |
| 12) | 69 * 248 - 69 * 48 = | | 12) ( 248 - 48) * 69 = 13800 |
| 13) | 87 * 65 + 87 * 35 = | | 13) ( 65 + 35) * 87 = 8700 |
| 14) | 161 * 77 - 77 * 61 = | | 14) ( 161 - 61) * 77 = 7700 |
| 15) | 161 * 71 - 61 * 71 = | | 15) ( 161 - 61) * 71 = 7100 |
| 16) | 72 * 70 + 70 * 28 = | | 16) ( 28 + 72) * 70 = 7000 |
| 17) | 31 * 44 + 69 * 44 = | | 17) ( 31 + 69) * 44 = 4400 |
| 18) | 155 * 45 - 45 * 55 = | | 18) ( 155 - 55) * 45 = 4500 |
| 19) | 88 * 75 + 88 * 125 = | | 19) ( 125 + 75) * 88 = 17600 |
| 20) | 35 * 27 + 27 * 65 = | | 20) ( 65 + 35) * 27 = 2700 |
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Score: ______________ | |
