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 March 26 2026
03:43:43 PM | Thursday March 26 2026
03:43:43 PMFlip Answers |
| 1) | 210 * 190 = | | 1) 200 * 200 - 10 * 10 = 39900 |
| 2) | 294 * 306 = | | 2) 300 * 300 - 6 * 6 = 89964 |
| 3) | 397 * 403 = | | 3) 400 * 400 - 3 * 3 = 159991 |
| 4) | 299 * 301 = | | 4) 300 * 300 - 1 * 1 = 89999 |
| 5) | 190 * 210 = | | 5) 200 * 200 - 10 * 10 = 39900 |
| 6) | 101 * 99 = | | 6) 100 * 100 - 1 * 1 = 9999 |
| 7) | 209 * 191 = | | 7) 200 * 200 - 9 * 9 = 39919 |
| 8) | 91 * 109 = | | 8) 100 * 100 - 9 * 9 = 9919 |
| 9) | 206 * 194 = | | 9) 200 * 200 - 6 * 6 = 39964 |
| 10) | 408 * 392 = | | 10) 400 * 400 - 8 * 8 = 159936 |
| 11) | 50 * 26 + 50 * 26 = | | 11) ( 50 + 50) * 26 = 2600 |
| 12) | 50 * 155 + 50 * 45 = | | 12) ( 155 + 45) * 50 = 10000 |
| 13) | 54 * 88 + 46 * 88 = | | 13) ( 46 + 54) * 88 = 8800 |
| 14) | 25 * 262 - 62 * 25 = | | 14) ( 262 - 62) * 25 = 5000 |
| 15) | 138 * 39 - 38 * 39 = | | 15) ( 138 - 38) * 39 = 3900 |
| 16) | 135 * 91 - 35 * 91 = | | 16) ( 135 - 35) * 91 = 9100 |
| 17) | 154 * 72 - 54 * 72 = | | 17) ( 154 - 54) * 72 = 7200 |
| 18) | 155 * 65 + 65 * 45 = | | 18) ( 155 + 45) * 65 = 13000 |
| 19) | 73 * 50 + 50 * 73 = | | 19) ( 50 + 50) * 73 = 7300 |
| 20) | 70 * 239 - 70 * 39 = | | 20) ( 239 - 39) * 70 = 14000 |
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Score: ______________ | |
