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 09 2026
08:51:35 PM | Thursday April 09 2026
08:51:35 PMFlip Answers |
| 1) | 399 * 401 = | | 1) 400 * 400 - 1 * 1 = 159999 |
| 2) | 206 * 194 = | | 2) 200 * 200 - 6 * 6 = 39964 |
| 3) | 293 * 307 = | | 3) 300 * 300 - 7 * 7 = 89951 |
| 4) | 295 * 305 = | | 4) 300 * 300 - 5 * 5 = 89975 |
| 5) | 95 * 105 = | | 5) 100 * 100 - 5 * 5 = 9975 |
| 6) | 109 * 91 = | | 6) 100 * 100 - 9 * 9 = 9919 |
| 7) | 399 * 401 = | | 7) 400 * 400 - 1 * 1 = 159999 |
| 8) | 291 * 309 = | | 8) 300 * 300 - 9 * 9 = 89919 |
| 9) | 195 * 205 = | | 9) 200 * 200 - 5 * 5 = 39975 |
| 10) | 91 * 109 = | | 10) 100 * 100 - 9 * 9 = 9919 |
| 11) | 150 * 45 - 45 * 50 = | | 11) ( 150 - 50) * 45 = 4500 |
| 12) | 132 * 70 + 68 * 70 = | | 12) ( 132 + 68) * 70 = 14000 |
| 13) | 143 * 96 - 43 * 96 = | | 13) ( 143 - 43) * 96 = 9600 |
| 14) | 74 * 148 - 74 * 48 = | | 14) ( 148 - 48) * 74 = 7400 |
| 15) | 142 * 36 - 36 * 42 = | | 15) ( 142 - 42) * 36 = 3600 |
| 16) | 138 * 87 - 87 * 38 = | | 16) ( 138 - 38) * 87 = 8700 |
| 17) | 59 * 90 + 90 * 41 = | | 17) ( 41 + 59) * 90 = 9000 |
| 18) | 33 * 147 + 33 * 53 = | | 18) ( 147 + 53) * 33 = 6600 |
| 19) | 96 * 37 + 63 * 96 = | | 19) ( 63 + 37) * 96 = 9600 |
| 20) | 43 * 87 + 57 * 87 = | | 20) ( 57 + 43) * 87 = 8700 |
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Score: ______________ | |
