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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Sunday December 14 2025
11:38:00 PM | Sunday December 14 2025
11:38:00 PMFlip Answers |
| 1) | 401 * 399 = | | 1) 400 * 400 - 1 * 1 = 159999 |
| 2) | 96 * 104 = | | 2) 100 * 100 - 4 * 4 = 9984 |
| 3) | 294 * 306 = | | 3) 300 * 300 - 6 * 6 = 89964 |
| 4) | 301 * 299 = | | 4) 300 * 300 - 1 * 1 = 89999 |
| 5) | 410 * 390 = | | 5) 400 * 400 - 10 * 10 = 159900 |
| 6) | 203 * 197 = | | 6) 200 * 200 - 3 * 3 = 39991 |
| 7) | 293 * 307 = | | 7) 300 * 300 - 7 * 7 = 89951 |
| 8) | 206 * 194 = | | 8) 200 * 200 - 6 * 6 = 39964 |
| 9) | 192 * 208 = | | 9) 200 * 200 - 8 * 8 = 39936 |
| 10) | 108 * 92 = | | 10) 100 * 100 - 8 * 8 = 9936 |
| 11) | 54 * 156 + 54 * 44 = | | 11) ( 156 + 44) * 54 = 10800 |
| 12) | 35 * 51 + 35 * 149 = | | 12) ( 149 + 51) * 35 = 7000 |
| 13) | 50 * 53 + 50 * 53 = | | 13) ( 50 + 50) * 53 = 5300 |
| 14) | 52 * 66 + 148 * 66 = | | 14) ( 148 + 52) * 66 = 13200 |
| 15) | 78 * 39 + 161 * 78 = | | 15) ( 161 + 39) * 78 = 15600 |
| 16) | 257 * 32 - 32 * 57 = | | 16) ( 257 - 57) * 32 = 6400 |
| 17) | 250 * 40 - 40 * 50 = | | 17) ( 250 - 50) * 40 = 8000 |
| 18) | 91 * 167 - 67 * 91 = | | 18) ( 167 - 67) * 91 = 9100 |
| 19) | 249 * 39 - 49 * 39 = | | 19) ( 249 - 49) * 39 = 7800 |
| 20) | 29 * 173 - 73 * 29 = | | 20) ( 173 - 73) * 29 = 2900 |
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Score: ______________ | |
