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 May 08 2026
12:53:52 PM | Friday May 08 2026
12:53:52 PMFlip Answers |
| 1) | 101 * 99 = | | 1) 100 * 100 - 1 * 1 = 9999 |
| 2) | 190 * 210 = | | 2) 200 * 200 - 10 * 10 = 39900 |
| 3) | 191 * 209 = | | 3) 200 * 200 - 9 * 9 = 39919 |
| 4) | 309 * 291 = | | 4) 300 * 300 - 9 * 9 = 89919 |
| 5) | 195 * 205 = | | 5) 200 * 200 - 5 * 5 = 39975 |
| 6) | 194 * 206 = | | 6) 200 * 200 - 6 * 6 = 39964 |
| 7) | 392 * 408 = | | 7) 400 * 400 - 8 * 8 = 159936 |
| 8) | 107 * 93 = | | 8) 100 * 100 - 7 * 7 = 9951 |
| 9) | 104 * 96 = | | 9) 100 * 100 - 4 * 4 = 9984 |
| 10) | 399 * 401 = | | 10) 400 * 400 - 1 * 1 = 159999 |
| 11) | 243 * 57 - 43 * 57 = | | 11) ( 243 - 43) * 57 = 11400 |
| 12) | 39 * 42 + 158 * 39 = | | 12) ( 158 + 42) * 39 = 7800 |
| 13) | 61 * 36 + 61 * 164 = | | 13) ( 164 + 36) * 61 = 12200 |
| 14) | 57 * 154 - 54 * 57 = | | 14) ( 154 - 54) * 57 = 5700 |
| 15) | 51 * 151 - 51 * 51 = | | 15) ( 151 - 51) * 51 = 5100 |
| 16) | 51 * 37 + 51 * 63 = | | 16) ( 37 + 63) * 51 = 5100 |
| 17) | 33 * 162 + 38 * 33 = | | 17) ( 162 + 38) * 33 = 6600 |
| 18) | 93 * 65 + 93 * 35 = | | 18) ( 35 + 65) * 93 = 9300 |
| 19) | 259 * 24 - 59 * 24 = | | 19) ( 259 - 59) * 24 = 4800 |
| 20) | 58 * 48 + 58 * 52 = | | 20) ( 52 + 48) * 58 = 5800 |
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Score: ______________ | |
