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
|
|
Sunday May 24 2026
11:19:56 PM | Sunday May 24 2026
11:19:56 PMFlip Answers |
| 1) | 205 * 195 = | | 1) 200 * 200 - 5 * 5 = 39975 |
| 2) | 310 * 290 = | | 2) 300 * 300 - 10 * 10 = 89900 |
| 3) | 192 * 208 = | | 3) 200 * 200 - 8 * 8 = 39936 |
| 4) | 407 * 393 = | | 4) 400 * 400 - 7 * 7 = 159951 |
| 5) | 95 * 105 = | | 5) 100 * 100 - 5 * 5 = 9975 |
| 6) | 293 * 307 = | | 6) 300 * 300 - 7 * 7 = 89951 |
| 7) | 396 * 404 = | | 7) 400 * 400 - 4 * 4 = 159984 |
| 8) | 105 * 95 = | | 8) 100 * 100 - 5 * 5 = 9975 |
| 9) | 402 * 398 = | | 9) 400 * 400 - 2 * 2 = 159996 |
| 10) | 292 * 308 = | | 10) 300 * 300 - 8 * 8 = 89936 |
| 11) | 60 * 42 + 40 * 42 = | | 11) ( 60 + 40) * 42 = 4200 |
| 12) | 94 * 253 - 94 * 53 = | | 12) ( 253 - 53) * 94 = 18800 |
| 13) | 163 * 50 - 63 * 50 = | | 13) ( 163 - 63) * 50 = 5000 |
| 14) | 41 * 50 + 50 * 59 = | | 14) ( 59 + 41) * 50 = 5000 |
| 15) | 78 * 59 + 78 * 141 = | | 15) ( 141 + 59) * 78 = 15600 |
| 16) | 22 * 144 + 22 * 56 = | | 16) ( 144 + 56) * 22 = 4400 |
| 17) | 68 * 49 + 132 * 49 = | | 17) ( 132 + 68) * 49 = 9800 |
| 18) | 236 * 94 - 94 * 36 = | | 18) ( 236 - 36) * 94 = 18800 |
| 19) | 45 * 259 - 59 * 45 = | | 19) ( 259 - 59) * 45 = 9000 |
| 20) | 141 * 21 - 41 * 21 = | | 20) ( 141 - 41) * 21 = 2100 |
|
Score: ______________ | |
