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 November 16 2025
04:08:25 AM | Sunday November 16 2025
04:08:25 AMFlip Answers |
| 1) | 396 * 404 = | | 1) 400 * 400 - 4 * 4 = 159984 |
| 2) | 207 * 193 = | | 2) 200 * 200 - 7 * 7 = 39951 |
| 3) | 390 * 410 = | | 3) 400 * 400 - 10 * 10 = 159900 |
| 4) | 203 * 197 = | | 4) 200 * 200 - 3 * 3 = 39991 |
| 5) | 402 * 398 = | | 5) 400 * 400 - 2 * 2 = 159996 |
| 6) | 203 * 197 = | | 6) 200 * 200 - 3 * 3 = 39991 |
| 7) | 296 * 304 = | | 7) 300 * 300 - 4 * 4 = 89984 |
| 8) | 190 * 210 = | | 8) 200 * 200 - 10 * 10 = 39900 |
| 9) | 210 * 190 = | | 9) 200 * 200 - 10 * 10 = 39900 |
| 10) | 299 * 301 = | | 10) 300 * 300 - 1 * 1 = 89999 |
| 11) | 156 * 85 - 56 * 85 = | | 11) ( 156 - 56) * 85 = 8500 |
| 12) | 151 * 70 - 70 * 51 = | | 12) ( 151 - 51) * 70 = 7000 |
| 13) | 267 * 91 - 67 * 91 = | | 13) ( 267 - 67) * 91 = 18200 |
| 14) | 155 * 96 - 96 * 55 = | | 14) ( 155 - 55) * 96 = 9600 |
| 15) | 238 * 94 - 38 * 94 = | | 15) ( 238 - 38) * 94 = 18800 |
| 16) | 80 * 45 + 155 * 80 = | | 16) ( 155 + 45) * 80 = 16000 |
| 17) | 126 * 87 + 74 * 87 = | | 17) ( 126 + 74) * 87 = 17400 |
| 18) | 96 * 39 + 96 * 161 = | | 18) ( 161 + 39) * 96 = 19200 |
| 19) | 65 * 128 + 65 * 72 = | | 19) ( 128 + 72) * 65 = 13000 |
| 20) | 97 * 45 + 97 * 155 = | | 20) ( 155 + 45) * 97 = 19400 |
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Score: ______________ | |
