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 March 06 2026
12:19:19 PM | Friday March 06 2026
12:19:19 PMFlip Answers |
| 1) | 408 * 392 = | | 1) 400 * 400 - 8 * 8 = 159936 |
| 2) | 293 * 307 = | | 2) 300 * 300 - 7 * 7 = 89951 |
| 3) | 192 * 208 = | | 3) 200 * 200 - 8 * 8 = 39936 |
| 4) | 206 * 194 = | | 4) 200 * 200 - 6 * 6 = 39964 |
| 5) | 290 * 310 = | | 5) 300 * 300 - 10 * 10 = 89900 |
| 6) | 310 * 290 = | | 6) 300 * 300 - 10 * 10 = 89900 |
| 7) | 209 * 191 = | | 7) 200 * 200 - 9 * 9 = 39919 |
| 8) | 299 * 301 = | | 8) 300 * 300 - 1 * 1 = 89999 |
| 9) | 306 * 294 = | | 9) 300 * 300 - 6 * 6 = 89964 |
| 10) | 295 * 305 = | | 10) 300 * 300 - 5 * 5 = 89975 |
| 11) | 260 * 39 - 60 * 39 = | | 11) ( 260 - 60) * 39 = 7800 |
| 12) | 35 * 275 - 35 * 75 = | | 12) ( 275 - 75) * 35 = 7000 |
| 13) | 61 * 69 + 139 * 69 = | | 13) ( 139 + 61) * 69 = 13800 |
| 14) | 32 * 262 - 62 * 32 = | | 14) ( 262 - 62) * 32 = 6400 |
| 15) | 167 * 67 - 67 * 67 = | | 15) ( 167 - 67) * 67 = 6700 |
| 16) | 69 * 80 + 80 * 31 = | | 16) ( 31 + 69) * 80 = 8000 |
| 17) | 65 * 79 + 79 * 35 = | | 17) ( 65 + 35) * 79 = 7900 |
| 18) | 147 * 33 + 33 * 53 = | | 18) ( 147 + 53) * 33 = 6600 |
| 19) | 72 * 50 + 72 * 50 = | | 19) ( 50 + 50) * 72 = 7200 |
| 20) | 44 * 32 + 32 * 56 = | | 20) ( 44 + 56) * 32 = 3200 |
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Score: ______________ | |
