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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Sunday September 20 2026
01:41:19 PM | Sunday September 20 2026
01:41:19 PMFlip Answers |
| 1) | 201 * 199 = | | 1) 200 * 200 - 1 * 1 = 39999 |
| 2) | 293 * 307 = | | 2) 300 * 300 - 7 * 7 = 89951 |
| 3) | 291 * 309 = | | 3) 300 * 300 - 9 * 9 = 89919 |
| 4) | 410 * 390 = | | 4) 400 * 400 - 10 * 10 = 159900 |
| 5) | 191 * 209 = | | 5) 200 * 200 - 9 * 9 = 39919 |
| 6) | 396 * 404 = | | 6) 400 * 400 - 4 * 4 = 159984 |
| 7) | 309 * 291 = | | 7) 300 * 300 - 9 * 9 = 89919 |
| 8) | 190 * 210 = | | 8) 200 * 200 - 10 * 10 = 39900 |
| 9) | 93 * 107 = | | 9) 100 * 100 - 7 * 7 = 9951 |
| 10) | 90 * 110 = | | 10) 100 * 100 - 10 * 10 = 9900 |
| 11) | 87 * 236 - 36 * 87 = | | 11) ( 236 - 36) * 87 = 17400 |
| 12) | 78 * 263 - 63 * 78 = | | 12) ( 263 - 63) * 78 = 15600 |
| 13) | 39 * 48 + 61 * 48 = | | 13) ( 61 + 39) * 48 = 4800 |
| 14) | 70 * 256 - 56 * 70 = | | 14) ( 256 - 56) * 70 = 14000 |
| 15) | 65 * 27 + 35 * 27 = | | 15) ( 65 + 35) * 27 = 2700 |
| 16) | 66 * 135 - 35 * 66 = | | 16) ( 135 - 35) * 66 = 6600 |
| 17) | 151 * 63 - 51 * 63 = | | 17) ( 151 - 51) * 63 = 6300 |
| 18) | 26 * 264 - 26 * 64 = | | 18) ( 264 - 64) * 26 = 5200 |
| 19) | 29 * 56 + 29 * 144 = | | 19) ( 144 + 56) * 29 = 5800 |
| 20) | 141 * 35 - 35 * 41 = | | 20) ( 141 - 41) * 35 = 3500 |
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Score: ______________ | |
