Math Main Page => Exercises - Math III
|
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
|
|
Monday December 01 2025
07:20:17 PM | Monday December 01 2025
07:20:17 PMFlip Answers |
| 1) | 392 * 408 = | | 1) 400 * 400 - 8 * 8 = 159936 |
| 2) | 402 * 398 = | | 2) 400 * 400 - 2 * 2 = 159996 |
| 3) | 102 * 98 = | | 3) 100 * 100 - 2 * 2 = 9996 |
| 4) | 303 * 297 = | | 4) 300 * 300 - 3 * 3 = 89991 |
| 5) | 204 * 196 = | | 5) 200 * 200 - 4 * 4 = 39984 |
| 6) | 410 * 390 = | | 6) 400 * 400 - 10 * 10 = 159900 |
| 7) | 398 * 402 = | | 7) 400 * 400 - 2 * 2 = 159996 |
| 8) | 204 * 196 = | | 8) 200 * 200 - 4 * 4 = 39984 |
| 9) | 194 * 206 = | | 9) 200 * 200 - 6 * 6 = 39964 |
| 10) | 294 * 306 = | | 10) 300 * 300 - 6 * 6 = 89964 |
| 11) | 262 * 45 - 45 * 62 = | | 11) ( 262 - 62) * 45 = 9000 |
| 12) | 68 * 47 + 53 * 68 = | | 12) ( 53 + 47) * 68 = 6800 |
| 13) | 141 * 96 - 96 * 41 = | | 13) ( 141 - 41) * 96 = 9600 |
| 14) | 148 * 84 + 84 * 52 = | | 14) ( 148 + 52) * 84 = 16800 |
| 15) | 63 * 27 + 27 * 37 = | | 15) ( 37 + 63) * 27 = 2700 |
| 16) | 90 * 152 - 52 * 90 = | | 16) ( 152 - 52) * 90 = 9000 |
| 17) | 243 * 97 - 97 * 43 = | | 17) ( 243 - 43) * 97 = 19400 |
| 18) | 159 * 31 - 59 * 31 = | | 18) ( 159 - 59) * 31 = 3100 |
| 19) | 38 * 36 + 38 * 164 = | | 19) ( 164 + 36) * 38 = 7600 |
| 20) | 164 * 72 - 64 * 72 = | | 20) ( 164 - 64) * 72 = 7200 |
|
Score: ______________ | |
