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 May 21 2026
12:45:35 PM | Thursday May 21 2026
12:45:35 PMFlip Answers |
| 1) | 395 * 405 = | | 1) 400 * 400 - 5 * 5 = 159975 |
| 2) | 192 * 208 = | | 2) 200 * 200 - 8 * 8 = 39936 |
| 3) | 205 * 195 = | | 3) 200 * 200 - 5 * 5 = 39975 |
| 4) | 92 * 108 = | | 4) 100 * 100 - 8 * 8 = 9936 |
| 5) | 94 * 106 = | | 5) 100 * 100 - 6 * 6 = 9964 |
| 6) | 196 * 204 = | | 6) 200 * 200 - 4 * 4 = 39984 |
| 7) | 192 * 208 = | | 7) 200 * 200 - 8 * 8 = 39936 |
| 8) | 210 * 190 = | | 8) 200 * 200 - 10 * 10 = 39900 |
| 9) | 403 * 397 = | | 9) 400 * 400 - 3 * 3 = 159991 |
| 10) | 106 * 94 = | | 10) 100 * 100 - 6 * 6 = 9964 |
| 11) | 73 * 173 - 73 * 73 = | | 11) ( 173 - 73) * 73 = 7300 |
| 12) | 91 * 162 + 91 * 38 = | | 12) ( 162 + 38) * 91 = 18200 |
| 13) | 137 * 38 - 38 * 37 = | | 13) ( 137 - 37) * 38 = 3800 |
| 14) | 265 * 96 - 96 * 65 = | | 14) ( 265 - 65) * 96 = 19200 |
| 15) | 64 * 91 + 91 * 36 = | | 15) ( 64 + 36) * 91 = 9100 |
| 16) | 252 * 53 - 53 * 52 = | | 16) ( 252 - 52) * 53 = 10600 |
| 17) | 34 * 158 + 34 * 42 = | | 17) ( 158 + 42) * 34 = 6800 |
| 18) | 73 * 75 + 73 * 25 = | | 18) ( 25 + 75) * 73 = 7300 |
| 19) | 33 * 161 - 61 * 33 = | | 19) ( 161 - 61) * 33 = 3300 |
| 20) | 52 * 50 + 48 * 50 = | | 20) ( 52 + 48) * 50 = 5000 |
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Score: ______________ | |
