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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Friday April 17 2026
06:02:21 AM | Friday April 17 2026
06:02:21 AMFlip Answers |
| 1) | 390 * 410 = | | 1) 400 * 400 - 10 * 10 = 159900 |
| 2) | 304 * 296 = | | 2) 300 * 300 - 4 * 4 = 89984 |
| 3) | 309 * 291 = | | 3) 300 * 300 - 9 * 9 = 89919 |
| 4) | 301 * 299 = | | 4) 300 * 300 - 1 * 1 = 89999 |
| 5) | 401 * 399 = | | 5) 400 * 400 - 1 * 1 = 159999 |
| 6) | 292 * 308 = | | 6) 300 * 300 - 8 * 8 = 89936 |
| 7) | 199 * 201 = | | 7) 200 * 200 - 1 * 1 = 39999 |
| 8) | 199 * 201 = | | 8) 200 * 200 - 1 * 1 = 39999 |
| 9) | 107 * 93 = | | 9) 100 * 100 - 7 * 7 = 9951 |
| 10) | 305 * 295 = | | 10) 300 * 300 - 5 * 5 = 89975 |
| 11) | 41 * 67 + 67 * 159 = | | 11) ( 159 + 41) * 67 = 13400 |
| 12) | 238 * 94 - 94 * 38 = | | 12) ( 238 - 38) * 94 = 18800 |
| 13) | 171 * 70 - 71 * 70 = | | 13) ( 171 - 71) * 70 = 7000 |
| 14) | 47 * 268 - 47 * 68 = | | 14) ( 268 - 68) * 47 = 9400 |
| 15) | 54 * 262 - 54 * 62 = | | 15) ( 262 - 62) * 54 = 10800 |
| 16) | 258 * 61 - 58 * 61 = | | 16) ( 258 - 58) * 61 = 12200 |
| 17) | 89 * 159 - 89 * 59 = | | 17) ( 159 - 59) * 89 = 8900 |
| 18) | 64 * 42 + 42 * 36 = | | 18) ( 36 + 64) * 42 = 4200 |
| 19) | 54 * 56 + 46 * 56 = | | 19) ( 54 + 46) * 56 = 5600 |
| 20) | 55 * 48 + 45 * 48 = | | 20) ( 45 + 55) * 48 = 4800 |
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Score: ______________ | |
