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 August 18 2026
11:51:44 PM | Tuesday August 18 2026
11:51:44 PMFlip Answers |
| 1) | 407 * 393 = | | 1) 400 * 400 - 7 * 7 = 159951 |
| 2) | 299 * 301 = | | 2) 300 * 300 - 1 * 1 = 89999 |
| 3) | 193 * 207 = | | 3) 200 * 200 - 7 * 7 = 39951 |
| 4) | 110 * 90 = | | 4) 100 * 100 - 10 * 10 = 9900 |
| 5) | 94 * 106 = | | 5) 100 * 100 - 6 * 6 = 9964 |
| 6) | 109 * 91 = | | 6) 100 * 100 - 9 * 9 = 9919 |
| 7) | 307 * 293 = | | 7) 300 * 300 - 7 * 7 = 89951 |
| 8) | 210 * 190 = | | 8) 200 * 200 - 10 * 10 = 39900 |
| 9) | 208 * 192 = | | 9) 200 * 200 - 8 * 8 = 39936 |
| 10) | 110 * 90 = | | 10) 100 * 100 - 10 * 10 = 9900 |
| 11) | 89 * 237 - 37 * 89 = | | 11) ( 237 - 37) * 89 = 17800 |
| 12) | 86 * 135 - 86 * 35 = | | 12) ( 135 - 35) * 86 = 8600 |
| 13) | 164 * 95 - 95 * 64 = | | 13) ( 164 - 64) * 95 = 9500 |
| 14) | 136 * 88 - 88 * 36 = | | 14) ( 136 - 36) * 88 = 8800 |
| 15) | 71 * 142 - 42 * 71 = | | 15) ( 142 - 42) * 71 = 7100 |
| 16) | 57 * 156 - 57 * 56 = | | 16) ( 156 - 56) * 57 = 5700 |
| 17) | 174 * 81 - 81 * 74 = | | 17) ( 174 - 74) * 81 = 8100 |
| 18) | 96 * 258 - 58 * 96 = | | 18) ( 258 - 58) * 96 = 19200 |
| 19) | 30 * 63 + 30 * 37 = | | 19) ( 63 + 37) * 30 = 3000 |
| 20) | 39 * 39 + 39 * 161 = | | 20) ( 161 + 39) * 39 = 7800 |
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Score: ______________ | |
