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 March 07 2026
06:10:54 PM | Saturday March 07 2026
06:10:54 PMFlip Answers |
| 1) | 193 * 207 = | | 1) 200 * 200 - 7 * 7 = 39951 |
| 2) | 405 * 395 = | | 2) 400 * 400 - 5 * 5 = 159975 |
| 3) | 309 * 291 = | | 3) 300 * 300 - 9 * 9 = 89919 |
| 4) | 302 * 298 = | | 4) 300 * 300 - 2 * 2 = 89996 |
| 5) | 390 * 410 = | | 5) 400 * 400 - 10 * 10 = 159900 |
| 6) | 202 * 198 = | | 6) 200 * 200 - 2 * 2 = 39996 |
| 7) | 394 * 406 = | | 7) 400 * 400 - 6 * 6 = 159964 |
| 8) | 104 * 96 = | | 8) 100 * 100 - 4 * 4 = 9984 |
| 9) | 292 * 308 = | | 9) 300 * 300 - 8 * 8 = 89936 |
| 10) | 406 * 394 = | | 10) 400 * 400 - 6 * 6 = 159964 |
| 11) | 25 * 96 + 75 * 96 = | | 11) ( 25 + 75) * 96 = 9600 |
| 12) | 140 * 68 + 60 * 68 = | | 12) ( 140 + 60) * 68 = 13600 |
| 13) | 37 * 41 + 63 * 41 = | | 13) ( 37 + 63) * 41 = 4100 |
| 14) | 50 * 74 + 50 * 74 = | | 14) ( 50 + 50) * 74 = 7400 |
| 15) | 237 * 72 - 37 * 72 = | | 15) ( 237 - 37) * 72 = 14400 |
| 16) | 72 * 47 + 128 * 47 = | | 16) ( 128 + 72) * 47 = 9400 |
| 17) | 82 * 64 + 36 * 82 = | | 17) ( 64 + 36) * 82 = 8200 |
| 18) | 138 * 32 - 32 * 38 = | | 18) ( 138 - 38) * 32 = 3200 |
| 19) | 165 * 59 - 65 * 59 = | | 19) ( 165 - 65) * 59 = 5900 |
| 20) | 164 * 64 + 36 * 64 = | | 20) ( 164 + 36) * 64 = 12800 |
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Score: ______________ | |
