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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Saturday January 24 2026
07:07:47 AM | Saturday January 24 2026
07:07:47 AMFlip Answers |
| 1) | 302 * 298 = | | 1) 300 * 300 - 2 * 2 = 89996 |
| 2) | 190 * 210 = | | 2) 200 * 200 - 10 * 10 = 39900 |
| 3) | 399 * 401 = | | 3) 400 * 400 - 1 * 1 = 159999 |
| 4) | 395 * 405 = | | 4) 400 * 400 - 5 * 5 = 159975 |
| 5) | 299 * 301 = | | 5) 300 * 300 - 1 * 1 = 89999 |
| 6) | 102 * 98 = | | 6) 100 * 100 - 2 * 2 = 9996 |
| 7) | 408 * 392 = | | 7) 400 * 400 - 8 * 8 = 159936 |
| 8) | 393 * 407 = | | 8) 400 * 400 - 7 * 7 = 159951 |
| 9) | 308 * 292 = | | 9) 300 * 300 - 8 * 8 = 89936 |
| 10) | 390 * 410 = | | 10) 400 * 400 - 10 * 10 = 159900 |
| 11) | 171 * 45 - 71 * 45 = | | 11) ( 171 - 71) * 45 = 4500 |
| 12) | 59 * 54 + 41 * 54 = | | 12) ( 59 + 41) * 54 = 5400 |
| 13) | 57 * 162 + 38 * 57 = | | 13) ( 162 + 38) * 57 = 11400 |
| 14) | 250 * 96 - 96 * 50 = | | 14) ( 250 - 50) * 96 = 19200 |
| 15) | 80 * 273 - 73 * 80 = | | 15) ( 273 - 73) * 80 = 16000 |
| 16) | 73 * 136 - 36 * 73 = | | 16) ( 136 - 36) * 73 = 7300 |
| 17) | 86 * 164 - 64 * 86 = | | 17) ( 164 - 64) * 86 = 8600 |
| 18) | 53 * 79 + 47 * 79 = | | 18) ( 53 + 47) * 79 = 7900 |
| 19) | 21 * 149 - 49 * 21 = | | 19) ( 149 - 49) * 21 = 2100 |
| 20) | 65 * 144 - 65 * 44 = | | 20) ( 144 - 44) * 65 = 6500 |
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Score: ______________ | |
