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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Thursday August 27 2026
07:25:35 AM | Thursday August 27 2026
07:25:35 AMFlip Answers |
| 1) | 399 * 401 = | | 1) 400 * 400 - 1 * 1 = 159999 |
| 2) | 201 * 199 = | | 2) 200 * 200 - 1 * 1 = 39999 |
| 3) | 301 * 299 = | | 3) 300 * 300 - 1 * 1 = 89999 |
| 4) | 308 * 292 = | | 4) 300 * 300 - 8 * 8 = 89936 |
| 5) | 204 * 196 = | | 5) 200 * 200 - 4 * 4 = 39984 |
| 6) | 103 * 97 = | | 6) 100 * 100 - 3 * 3 = 9991 |
| 7) | 203 * 197 = | | 7) 200 * 200 - 3 * 3 = 39991 |
| 8) | 297 * 303 = | | 8) 300 * 300 - 3 * 3 = 89991 |
| 9) | 102 * 98 = | | 9) 100 * 100 - 2 * 2 = 9996 |
| 10) | 398 * 402 = | | 10) 400 * 400 - 2 * 2 = 159996 |
| 11) | 52 * 56 + 48 * 56 = | | 11) ( 52 + 48) * 56 = 5600 |
| 12) | 29 * 78 + 78 * 71 = | | 12) ( 29 + 71) * 78 = 7800 |
| 13) | 80 * 136 - 80 * 36 = | | 13) ( 136 - 36) * 80 = 8000 |
| 14) | 80 * 238 - 38 * 80 = | | 14) ( 238 - 38) * 80 = 16000 |
| 15) | 263 * 91 - 91 * 63 = | | 15) ( 263 - 63) * 91 = 18200 |
| 16) | 23 * 41 + 23 * 59 = | | 16) ( 41 + 59) * 23 = 2300 |
| 17) | 93 * 159 + 41 * 93 = | | 17) ( 159 + 41) * 93 = 18600 |
| 18) | 175 * 38 - 38 * 75 = | | 18) ( 175 - 75) * 38 = 3800 |
| 19) | 95 * 273 - 73 * 95 = | | 19) ( 273 - 73) * 95 = 19000 |
| 20) | 57 * 256 - 57 * 56 = | | 20) ( 256 - 56) * 57 = 11400 |
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Score: ______________ | |
