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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Thursday December 11 2025
05:18:54 AM | Thursday December 11 2025
05:18:54 AMFlip Answers |
| 1) | 98 * 102 = | | 1) 100 * 100 - 2 * 2 = 9996 |
| 2) | 98 * 102 = | | 2) 100 * 100 - 2 * 2 = 9996 |
| 3) | 402 * 398 = | | 3) 400 * 400 - 2 * 2 = 159996 |
| 4) | 91 * 109 = | | 4) 100 * 100 - 9 * 9 = 9919 |
| 5) | 301 * 299 = | | 5) 300 * 300 - 1 * 1 = 89999 |
| 6) | 101 * 99 = | | 6) 100 * 100 - 1 * 1 = 9999 |
| 7) | 391 * 409 = | | 7) 400 * 400 - 9 * 9 = 159919 |
| 8) | 203 * 197 = | | 8) 200 * 200 - 3 * 3 = 39991 |
| 9) | 407 * 393 = | | 9) 400 * 400 - 7 * 7 = 159951 |
| 10) | 395 * 405 = | | 10) 400 * 400 - 5 * 5 = 159975 |
| 11) | 151 * 91 - 91 * 51 = | | 11) ( 151 - 51) * 91 = 9100 |
| 12) | 30 * 264 - 30 * 64 = | | 12) ( 264 - 64) * 30 = 6000 |
| 13) | 265 * 85 - 85 * 65 = | | 13) ( 265 - 65) * 85 = 17000 |
| 14) | 91 * 253 - 91 * 53 = | | 14) ( 253 - 53) * 91 = 18200 |
| 15) | 88 * 169 - 69 * 88 = | | 15) ( 169 - 69) * 88 = 8800 |
| 16) | 267 * 85 - 67 * 85 = | | 16) ( 267 - 67) * 85 = 17000 |
| 17) | 238 * 92 - 38 * 92 = | | 17) ( 238 - 38) * 92 = 18400 |
| 18) | 149 * 49 - 49 * 49 = | | 18) ( 149 - 49) * 49 = 4900 |
| 19) | 151 * 23 - 23 * 51 = | | 19) ( 151 - 51) * 23 = 2300 |
| 20) | 141 * 76 + 76 * 59 = | | 20) ( 141 + 59) * 76 = 15200 |
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Score: ______________ | |
