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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Monday April 13 2026
03:37:55 AM | Monday April 13 2026
03:37:55 AMFlip Answers |
| 1) | 205 * 195 = | | 1) 200 * 200 - 5 * 5 = 39975 |
| 2) | 90 * 110 = | | 2) 100 * 100 - 10 * 10 = 9900 |
| 3) | 192 * 208 = | | 3) 200 * 200 - 8 * 8 = 39936 |
| 4) | 207 * 193 = | | 4) 200 * 200 - 7 * 7 = 39951 |
| 5) | 104 * 96 = | | 5) 100 * 100 - 4 * 4 = 9984 |
| 6) | 98 * 102 = | | 6) 100 * 100 - 2 * 2 = 9996 |
| 7) | 92 * 108 = | | 7) 100 * 100 - 8 * 8 = 9936 |
| 8) | 407 * 393 = | | 8) 400 * 400 - 7 * 7 = 159951 |
| 9) | 309 * 291 = | | 9) 300 * 300 - 9 * 9 = 89919 |
| 10) | 201 * 199 = | | 10) 200 * 200 - 1 * 1 = 39999 |
| 11) | 69 * 28 + 69 * 72 = | | 11) ( 28 + 72) * 69 = 6900 |
| 12) | 138 * 28 - 38 * 28 = | | 12) ( 138 - 38) * 28 = 2800 |
| 13) | 72 * 129 + 71 * 72 = | | 13) ( 129 + 71) * 72 = 14400 |
| 14) | 25 * 175 - 75 * 25 = | | 14) ( 175 - 75) * 25 = 2500 |
| 15) | 65 * 55 + 45 * 65 = | | 15) ( 55 + 45) * 65 = 6500 |
| 16) | 262 * 70 - 62 * 70 = | | 16) ( 262 - 62) * 70 = 14000 |
| 17) | 54 * 252 - 54 * 52 = | | 17) ( 252 - 52) * 54 = 10800 |
| 18) | 155 * 48 + 45 * 48 = | | 18) ( 155 + 45) * 48 = 9600 |
| 19) | 76 * 272 - 72 * 76 = | | 19) ( 272 - 72) * 76 = 15200 |
| 20) | 243 * 68 - 43 * 68 = | | 20) ( 243 - 43) * 68 = 13600 |
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Score: ______________ | |
