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 January 30 2026
07:13:19 AM | Friday January 30 2026
07:13:19 AMFlip Answers |
| 1) | 207 * 193 = | | 1) 200 * 200 - 7 * 7 = 39951 |
| 2) | 194 * 206 = | | 2) 200 * 200 - 6 * 6 = 39964 |
| 3) | 407 * 393 = | | 3) 400 * 400 - 7 * 7 = 159951 |
| 4) | 392 * 408 = | | 4) 400 * 400 - 8 * 8 = 159936 |
| 5) | 110 * 90 = | | 5) 100 * 100 - 10 * 10 = 9900 |
| 6) | 201 * 199 = | | 6) 200 * 200 - 1 * 1 = 39999 |
| 7) | 96 * 104 = | | 7) 100 * 100 - 4 * 4 = 9984 |
| 8) | 390 * 410 = | | 8) 400 * 400 - 10 * 10 = 159900 |
| 9) | 192 * 208 = | | 9) 200 * 200 - 8 * 8 = 39936 |
| 10) | 202 * 198 = | | 10) 200 * 200 - 2 * 2 = 39996 |
| 11) | 73 * 58 + 42 * 73 = | | 11) ( 58 + 42) * 73 = 7300 |
| 12) | 138 * 84 + 62 * 84 = | | 12) ( 138 + 62) * 84 = 16800 |
| 13) | 164 * 54 - 64 * 54 = | | 13) ( 164 - 64) * 54 = 5400 |
| 14) | 39 * 37 + 37 * 61 = | | 14) ( 39 + 61) * 37 = 3700 |
| 15) | 79 * 43 + 79 * 57 = | | 15) ( 57 + 43) * 79 = 7900 |
| 16) | 159 * 47 + 47 * 41 = | | 16) ( 159 + 41) * 47 = 9400 |
| 17) | 84 * 148 - 48 * 84 = | | 17) ( 148 - 48) * 84 = 8400 |
| 18) | 48 * 260 - 48 * 60 = | | 18) ( 260 - 60) * 48 = 9600 |
| 19) | 50 * 128 + 72 * 50 = | | 19) ( 128 + 72) * 50 = 10000 |
| 20) | 48 * 71 + 29 * 48 = | | 20) ( 29 + 71) * 48 = 4800 |
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Score: ______________ | |
