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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Tuesday February 24 2026
07:23:15 PM | Tuesday February 24 2026
07:23:15 PMFlip Answers |
| 1) | 209 * 191 = | | 1) 200 * 200 - 9 * 9 = 39919 |
| 2) | 401 * 399 = | | 2) 400 * 400 - 1 * 1 = 159999 |
| 3) | 291 * 309 = | | 3) 300 * 300 - 9 * 9 = 89919 |
| 4) | 202 * 198 = | | 4) 200 * 200 - 2 * 2 = 39996 |
| 5) | 96 * 104 = | | 5) 100 * 100 - 4 * 4 = 9984 |
| 6) | 309 * 291 = | | 6) 300 * 300 - 9 * 9 = 89919 |
| 7) | 403 * 397 = | | 7) 400 * 400 - 3 * 3 = 159991 |
| 8) | 397 * 403 = | | 8) 400 * 400 - 3 * 3 = 159991 |
| 9) | 401 * 399 = | | 9) 400 * 400 - 1 * 1 = 159999 |
| 10) | 393 * 407 = | | 10) 400 * 400 - 7 * 7 = 159951 |
| 11) | 139 * 93 - 93 * 39 = | | 11) ( 139 - 39) * 93 = 9300 |
| 12) | 51 * 67 + 33 * 51 = | | 12) ( 33 + 67) * 51 = 5100 |
| 13) | 44 * 64 + 44 * 136 = | | 13) ( 136 + 64) * 44 = 8800 |
| 14) | 26 * 49 + 26 * 151 = | | 14) ( 151 + 49) * 26 = 5200 |
| 15) | 76 * 41 + 76 * 159 = | | 15) ( 159 + 41) * 76 = 15200 |
| 16) | 44 * 58 + 56 * 58 = | | 16) ( 56 + 44) * 58 = 5800 |
| 17) | 25 * 272 - 25 * 72 = | | 17) ( 272 - 72) * 25 = 5000 |
| 18) | 91 * 66 + 134 * 91 = | | 18) ( 134 + 66) * 91 = 18200 |
| 19) | 56 * 69 + 56 * 131 = | | 19) ( 131 + 69) * 56 = 11200 |
| 20) | 58 * 273 - 73 * 58 = | | 20) ( 273 - 73) * 58 = 11600 |
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Score: ______________ | |
