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
|
|
Wednesday May 20 2026
04:26:26 AM | Wednesday May 20 2026
04:26:26 AMFlip Answers |
| 1) | 190 * 210 = | | 1) 200 * 200 - 10 * 10 = 39900 |
| 2) | 293 * 307 = | | 2) 300 * 300 - 7 * 7 = 89951 |
| 3) | 291 * 309 = | | 3) 300 * 300 - 9 * 9 = 89919 |
| 4) | 307 * 293 = | | 4) 300 * 300 - 7 * 7 = 89951 |
| 5) | 190 * 210 = | | 5) 200 * 200 - 10 * 10 = 39900 |
| 6) | 110 * 90 = | | 6) 100 * 100 - 10 * 10 = 9900 |
| 7) | 306 * 294 = | | 7) 300 * 300 - 6 * 6 = 89964 |
| 8) | 309 * 291 = | | 8) 300 * 300 - 9 * 9 = 89919 |
| 9) | 393 * 407 = | | 9) 400 * 400 - 7 * 7 = 159951 |
| 10) | 396 * 404 = | | 10) 400 * 400 - 4 * 4 = 159984 |
| 11) | 72 * 241 - 41 * 72 = | | 11) ( 241 - 41) * 72 = 14400 |
| 12) | 44 * 51 + 149 * 44 = | | 12) ( 149 + 51) * 44 = 8800 |
| 13) | 42 * 56 + 58 * 56 = | | 13) ( 42 + 58) * 56 = 5600 |
| 14) | 89 * 38 + 162 * 89 = | | 14) ( 162 + 38) * 89 = 17800 |
| 15) | 81 * 50 + 81 * 150 = | | 15) ( 150 + 50) * 81 = 16200 |
| 16) | 72 * 70 + 72 * 130 = | | 16) ( 130 + 70) * 72 = 14400 |
| 17) | 60 * 237 - 37 * 60 = | | 17) ( 237 - 37) * 60 = 12000 |
| 18) | 36 * 258 - 58 * 36 = | | 18) ( 258 - 58) * 36 = 7200 |
| 19) | 33 * 240 - 40 * 33 = | | 19) ( 240 - 40) * 33 = 6600 |
| 20) | 23 * 266 - 23 * 66 = | | 20) ( 266 - 66) * 23 = 4600 |
|
Score: ______________ | |
