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 September 19 2026
11:45:11 AM | Saturday September 19 2026
11:45:11 AMFlip Answers |
| 1) | 398 * 402 = | | 1) 400 * 400 - 2 * 2 = 159996 |
| 2) | 305 * 295 = | | 2) 300 * 300 - 5 * 5 = 89975 |
| 3) | 190 * 210 = | | 3) 200 * 200 - 10 * 10 = 39900 |
| 4) | 296 * 304 = | | 4) 300 * 300 - 4 * 4 = 89984 |
| 5) | 199 * 201 = | | 5) 200 * 200 - 1 * 1 = 39999 |
| 6) | 190 * 210 = | | 6) 200 * 200 - 10 * 10 = 39900 |
| 7) | 390 * 410 = | | 7) 400 * 400 - 10 * 10 = 159900 |
| 8) | 306 * 294 = | | 8) 300 * 300 - 6 * 6 = 89964 |
| 9) | 294 * 306 = | | 9) 300 * 300 - 6 * 6 = 89964 |
| 10) | 201 * 199 = | | 10) 200 * 200 - 1 * 1 = 39999 |
| 11) | 43 * 53 + 43 * 47 = | | 11) ( 47 + 53) * 43 = 4300 |
| 12) | 263 * 30 - 30 * 63 = | | 12) ( 263 - 63) * 30 = 6000 |
| 13) | 258 * 72 - 72 * 58 = | | 13) ( 258 - 58) * 72 = 14400 |
| 14) | 165 * 71 - 65 * 71 = | | 14) ( 165 - 65) * 71 = 7100 |
| 15) | 88 * 171 - 71 * 88 = | | 15) ( 171 - 71) * 88 = 8800 |
| 16) | 162 * 74 + 38 * 74 = | | 16) ( 162 + 38) * 74 = 14800 |
| 17) | 263 * 61 - 63 * 61 = | | 17) ( 263 - 63) * 61 = 12200 |
| 18) | 85 * 259 - 85 * 59 = | | 18) ( 259 - 59) * 85 = 17000 |
| 19) | 29 * 91 + 71 * 91 = | | 19) ( 29 + 71) * 91 = 9100 |
| 20) | 42 * 40 + 42 * 60 = | | 20) ( 40 + 60) * 42 = 4200 |
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Score: ______________ | |
