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 September 25 2026
11:32:19 PM | Friday September 25 2026
11:32:19 PMFlip Answers |
| 1) | 394 * 406 = | | 1) 400 * 400 - 6 * 6 = 159964 |
| 2) | 197 * 203 = | | 2) 200 * 200 - 3 * 3 = 39991 |
| 3) | 392 * 408 = | | 3) 400 * 400 - 8 * 8 = 159936 |
| 4) | 92 * 108 = | | 4) 100 * 100 - 8 * 8 = 9936 |
| 5) | 201 * 199 = | | 5) 200 * 200 - 1 * 1 = 39999 |
| 6) | 402 * 398 = | | 6) 400 * 400 - 2 * 2 = 159996 |
| 7) | 390 * 410 = | | 7) 400 * 400 - 10 * 10 = 159900 |
| 8) | 190 * 210 = | | 8) 200 * 200 - 10 * 10 = 39900 |
| 9) | 91 * 109 = | | 9) 100 * 100 - 9 * 9 = 9919 |
| 10) | 107 * 93 = | | 10) 100 * 100 - 7 * 7 = 9951 |
| 11) | 268 * 97 - 68 * 97 = | | 11) ( 268 - 68) * 97 = 19400 |
| 12) | 31 * 97 + 69 * 97 = | | 12) ( 31 + 69) * 97 = 9700 |
| 13) | 44 * 257 - 57 * 44 = | | 13) ( 257 - 57) * 44 = 8800 |
| 14) | 91 * 39 + 61 * 91 = | | 14) ( 39 + 61) * 91 = 9100 |
| 15) | 143 * 31 + 31 * 57 = | | 15) ( 143 + 57) * 31 = 6200 |
| 16) | 267 * 97 - 67 * 97 = | | 16) ( 267 - 67) * 97 = 19400 |
| 17) | 165 * 44 - 44 * 65 = | | 17) ( 165 - 65) * 44 = 4400 |
| 18) | 144 * 48 + 56 * 48 = | | 18) ( 144 + 56) * 48 = 9600 |
| 19) | 56 * 56 + 56 * 44 = | | 19) ( 56 + 44) * 56 = 5600 |
| 20) | 44 * 51 + 49 * 44 = | | 20) ( 51 + 49) * 44 = 4400 |
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Score: ______________ | |
