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 January 23 2026
11:05:12 AM | Friday January 23 2026
11:05:12 AMFlip Answers |
| 1) | 102 * 98 = | | 1) 100 * 100 - 2 * 2 = 9996 |
| 2) | 410 * 390 = | | 2) 400 * 400 - 10 * 10 = 159900 |
| 3) | 205 * 195 = | | 3) 200 * 200 - 5 * 5 = 39975 |
| 4) | 295 * 305 = | | 4) 300 * 300 - 5 * 5 = 89975 |
| 5) | 91 * 109 = | | 5) 100 * 100 - 9 * 9 = 9919 |
| 6) | 301 * 299 = | | 6) 300 * 300 - 1 * 1 = 89999 |
| 7) | 303 * 297 = | | 7) 300 * 300 - 3 * 3 = 89991 |
| 8) | 402 * 398 = | | 8) 400 * 400 - 2 * 2 = 159996 |
| 9) | 391 * 409 = | | 9) 400 * 400 - 9 * 9 = 159919 |
| 10) | 299 * 301 = | | 10) 300 * 300 - 1 * 1 = 89999 |
| 11) | 59 * 94 + 41 * 94 = | | 11) ( 59 + 41) * 94 = 9400 |
| 12) | 26 * 79 + 74 * 79 = | | 12) ( 26 + 74) * 79 = 7900 |
| 13) | 70 * 45 + 155 * 70 = | | 13) ( 155 + 45) * 70 = 14000 |
| 14) | 50 * 127 + 50 * 73 = | | 14) ( 127 + 73) * 50 = 10000 |
| 15) | 65 * 43 + 57 * 65 = | | 15) ( 43 + 57) * 65 = 6500 |
| 16) | 84 * 42 + 84 * 158 = | | 16) ( 158 + 42) * 84 = 16800 |
| 17) | 96 * 265 - 65 * 96 = | | 17) ( 265 - 65) * 96 = 19200 |
| 18) | 245 * 41 - 41 * 45 = | | 18) ( 245 - 45) * 41 = 8200 |
| 19) | 253 * 64 - 64 * 53 = | | 19) ( 253 - 53) * 64 = 12800 |
| 20) | 242 * 97 - 97 * 42 = | | 20) ( 242 - 42) * 97 = 19400 |
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Score: ______________ | |
