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 March 25 2026
11:52:41 PM | Wednesday March 25 2026
11:52:41 PMFlip Answers |
| 1) | 393 * 407 = | | 1) 400 * 400 - 7 * 7 = 159951 |
| 2) | 194 * 206 = | | 2) 200 * 200 - 6 * 6 = 39964 |
| 3) | 310 * 290 = | | 3) 300 * 300 - 10 * 10 = 89900 |
| 4) | 410 * 390 = | | 4) 400 * 400 - 10 * 10 = 159900 |
| 5) | 307 * 293 = | | 5) 300 * 300 - 7 * 7 = 89951 |
| 6) | 396 * 404 = | | 6) 400 * 400 - 4 * 4 = 159984 |
| 7) | 405 * 395 = | | 7) 400 * 400 - 5 * 5 = 159975 |
| 8) | 101 * 99 = | | 8) 100 * 100 - 1 * 1 = 9999 |
| 9) | 193 * 207 = | | 9) 200 * 200 - 7 * 7 = 39951 |
| 10) | 308 * 292 = | | 10) 300 * 300 - 8 * 8 = 89936 |
| 11) | 96 * 75 + 96 * 125 = | | 11) ( 125 + 75) * 96 = 19200 |
| 12) | 262 * 64 - 62 * 64 = | | 12) ( 262 - 62) * 64 = 12800 |
| 13) | 175 * 68 - 68 * 75 = | | 13) ( 175 - 75) * 68 = 6800 |
| 14) | 62 * 37 + 163 * 62 = | | 14) ( 163 + 37) * 62 = 12400 |
| 15) | 160 * 92 - 92 * 60 = | | 15) ( 160 - 60) * 92 = 9200 |
| 16) | 50 * 29 + 50 * 71 = | | 16) ( 29 + 71) * 50 = 5000 |
| 17) | 66 * 61 + 39 * 66 = | | 17) ( 39 + 61) * 66 = 6600 |
| 18) | 52 * 150 - 50 * 52 = | | 18) ( 150 - 50) * 52 = 5200 |
| 19) | 264 * 39 - 39 * 64 = | | 19) ( 264 - 64) * 39 = 7800 |
| 20) | 30 * 37 + 163 * 30 = | | 20) ( 163 + 37) * 30 = 6000 |
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Score: ______________ | |
