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 April 02 2026
03:52:16 AM | Thursday April 02 2026
03:52:16 AMFlip Answers |
| 1) | 305 * 295 = | | 1) 300 * 300 - 5 * 5 = 89975 |
| 2) | 298 * 302 = | | 2) 300 * 300 - 2 * 2 = 89996 |
| 3) | 106 * 94 = | | 3) 100 * 100 - 6 * 6 = 9964 |
| 4) | 208 * 192 = | | 4) 200 * 200 - 8 * 8 = 39936 |
| 5) | 210 * 190 = | | 5) 200 * 200 - 10 * 10 = 39900 |
| 6) | 109 * 91 = | | 6) 100 * 100 - 9 * 9 = 9919 |
| 7) | 310 * 290 = | | 7) 300 * 300 - 10 * 10 = 89900 |
| 8) | 395 * 405 = | | 8) 400 * 400 - 5 * 5 = 159975 |
| 9) | 302 * 298 = | | 9) 300 * 300 - 2 * 2 = 89996 |
| 10) | 202 * 198 = | | 10) 200 * 200 - 2 * 2 = 39996 |
| 11) | 21 * 39 + 61 * 21 = | | 11) ( 61 + 39) * 21 = 2100 |
| 12) | 41 * 93 + 93 * 159 = | | 12) ( 159 + 41) * 93 = 18600 |
| 13) | 43 * 130 + 43 * 70 = | | 13) ( 130 + 70) * 43 = 8600 |
| 14) | 251 * 36 - 51 * 36 = | | 14) ( 251 - 51) * 36 = 7200 |
| 15) | 46 * 87 + 87 * 54 = | | 15) ( 54 + 46) * 87 = 8700 |
| 16) | 55 * 245 - 45 * 55 = | | 16) ( 245 - 45) * 55 = 11000 |
| 17) | 77 * 62 + 138 * 77 = | | 17) ( 138 + 62) * 77 = 15400 |
| 18) | 239 * 66 - 39 * 66 = | | 18) ( 239 - 39) * 66 = 13200 |
| 19) | 85 * 69 + 131 * 85 = | | 19) ( 131 + 69) * 85 = 17000 |
| 20) | 75 * 268 - 68 * 75 = | | 20) ( 268 - 68) * 75 = 15000 |
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Score: ______________ | |
