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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Friday October 16 2026
10:29:02 PM | Friday October 16 2026
10:29:02 PMFlip Answers |
| 1) | 290 * 310 = | | 1) 300 * 300 - 10 * 10 = 89900 |
| 2) | 407 * 393 = | | 2) 400 * 400 - 7 * 7 = 159951 |
| 3) | 90 * 110 = | | 3) 100 * 100 - 10 * 10 = 9900 |
| 4) | 101 * 99 = | | 4) 100 * 100 - 1 * 1 = 9999 |
| 5) | 202 * 198 = | | 5) 200 * 200 - 2 * 2 = 39996 |
| 6) | 293 * 307 = | | 6) 300 * 300 - 7 * 7 = 89951 |
| 7) | 390 * 410 = | | 7) 400 * 400 - 10 * 10 = 159900 |
| 8) | 291 * 309 = | | 8) 300 * 300 - 9 * 9 = 89919 |
| 9) | 104 * 96 = | | 9) 100 * 100 - 4 * 4 = 9984 |
| 10) | 199 * 201 = | | 10) 200 * 200 - 1 * 1 = 39999 |
| 11) | 239 * 82 - 82 * 39 = | | 11) ( 239 - 39) * 82 = 16400 |
| 12) | 50 * 40 + 160 * 50 = | | 12) ( 160 + 40) * 50 = 10000 |
| 13) | 145 * 89 + 89 * 55 = | | 13) ( 145 + 55) * 89 = 17800 |
| 14) | 259 * 45 - 45 * 59 = | | 14) ( 259 - 59) * 45 = 9000 |
| 15) | 30 * 65 + 30 * 35 = | | 15) ( 65 + 35) * 30 = 3000 |
| 16) | 158 * 46 + 42 * 46 = | | 16) ( 158 + 42) * 46 = 9200 |
| 17) | 22 * 26 + 74 * 22 = | | 17) ( 26 + 74) * 22 = 2200 |
| 18) | 51 * 56 + 144 * 51 = | | 18) ( 144 + 56) * 51 = 10200 |
| 19) | 59 * 132 + 68 * 59 = | | 19) ( 132 + 68) * 59 = 11800 |
| 20) | 55 * 62 + 62 * 45 = | | 20) ( 55 + 45) * 62 = 6200 |
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Score: ______________ | |
