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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Tuesday November 03 2026
10:44:37 AM | Tuesday November 03 2026
10:44:37 AMFlip Answers |
| 1) | 310 * 290 = | | 1) 300 * 300 - 10 * 10 = 89900 |
| 2) | 201 * 199 = | | 2) 200 * 200 - 1 * 1 = 39999 |
| 3) | 405 * 395 = | | 3) 400 * 400 - 5 * 5 = 159975 |
| 4) | 392 * 408 = | | 4) 400 * 400 - 8 * 8 = 159936 |
| 5) | 395 * 405 = | | 5) 400 * 400 - 5 * 5 = 159975 |
| 6) | 298 * 302 = | | 6) 300 * 300 - 2 * 2 = 89996 |
| 7) | 304 * 296 = | | 7) 300 * 300 - 4 * 4 = 89984 |
| 8) | 291 * 309 = | | 8) 300 * 300 - 9 * 9 = 89919 |
| 9) | 409 * 391 = | | 9) 400 * 400 - 9 * 9 = 159919 |
| 10) | 293 * 307 = | | 10) 300 * 300 - 7 * 7 = 89951 |
| 11) | 264 * 50 - 64 * 50 = | | 11) ( 264 - 64) * 50 = 10000 |
| 12) | 54 * 258 - 58 * 54 = | | 12) ( 258 - 58) * 54 = 10800 |
| 13) | 68 * 252 - 52 * 68 = | | 13) ( 252 - 52) * 68 = 13600 |
| 14) | 79 * 75 + 25 * 79 = | | 14) ( 25 + 75) * 79 = 7900 |
| 15) | 87 * 170 - 87 * 70 = | | 15) ( 170 - 70) * 87 = 8700 |
| 16) | 29 * 255 - 29 * 55 = | | 16) ( 255 - 55) * 29 = 5800 |
| 17) | 65 * 38 + 38 * 35 = | | 17) ( 65 + 35) * 38 = 3800 |
| 18) | 65 * 254 - 54 * 65 = | | 18) ( 254 - 54) * 65 = 13000 |
| 19) | 59 * 145 - 45 * 59 = | | 19) ( 145 - 45) * 59 = 5900 |
| 20) | 165 * 38 - 38 * 65 = | | 20) ( 165 - 65) * 38 = 3800 |
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Score: ______________ | |
