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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Monday January 26 2026
09:42:27 PM | Monday January 26 2026
09:42:27 PMFlip Answers |
| 1) | 301 * 299 = | | 1) 300 * 300 - 1 * 1 = 89999 |
| 2) | 403 * 397 = | | 2) 400 * 400 - 3 * 3 = 159991 |
| 3) | 399 * 401 = | | 3) 400 * 400 - 1 * 1 = 159999 |
| 4) | 393 * 407 = | | 4) 400 * 400 - 7 * 7 = 159951 |
| 5) | 399 * 401 = | | 5) 400 * 400 - 1 * 1 = 159999 |
| 6) | 303 * 297 = | | 6) 300 * 300 - 3 * 3 = 89991 |
| 7) | 307 * 293 = | | 7) 300 * 300 - 7 * 7 = 89951 |
| 8) | 192 * 208 = | | 8) 200 * 200 - 8 * 8 = 39936 |
| 9) | 97 * 103 = | | 9) 100 * 100 - 3 * 3 = 9991 |
| 10) | 292 * 308 = | | 10) 300 * 300 - 8 * 8 = 89936 |
| 11) | 90 * 171 - 71 * 90 = | | 11) ( 171 - 71) * 90 = 9000 |
| 12) | 56 * 22 + 144 * 22 = | | 12) ( 144 + 56) * 22 = 4400 |
| 13) | 49 * 30 + 51 * 30 = | | 13) ( 51 + 49) * 30 = 3000 |
| 14) | 149 * 46 + 51 * 46 = | | 14) ( 149 + 51) * 46 = 9200 |
| 15) | 74 * 168 - 74 * 68 = | | 15) ( 168 - 68) * 74 = 7400 |
| 16) | 155 * 56 - 55 * 56 = | | 16) ( 155 - 55) * 56 = 5600 |
| 17) | 35 * 81 + 65 * 81 = | | 17) ( 35 + 65) * 81 = 8100 |
| 18) | 140 * 49 - 49 * 40 = | | 18) ( 140 - 40) * 49 = 4900 |
| 19) | 93 * 60 + 40 * 93 = | | 19) ( 40 + 60) * 93 = 9300 |
| 20) | 275 * 67 - 67 * 75 = | | 20) ( 275 - 75) * 67 = 13400 |
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Score: ______________ | |
