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
|
|
Tuesday February 10 2026
04:31:54 AM | Tuesday February 10 2026
04:31:54 AMFlip Answers |
| 1) | 390 * 410 = | | 1) 400 * 400 - 10 * 10 = 159900 |
| 2) | 395 * 405 = | | 2) 400 * 400 - 5 * 5 = 159975 |
| 3) | 307 * 293 = | | 3) 300 * 300 - 7 * 7 = 89951 |
| 4) | 396 * 404 = | | 4) 400 * 400 - 4 * 4 = 159984 |
| 5) | 97 * 103 = | | 5) 100 * 100 - 3 * 3 = 9991 |
| 6) | 291 * 309 = | | 6) 300 * 300 - 9 * 9 = 89919 |
| 7) | 410 * 390 = | | 7) 400 * 400 - 10 * 10 = 159900 |
| 8) | 401 * 399 = | | 8) 400 * 400 - 1 * 1 = 159999 |
| 9) | 96 * 104 = | | 9) 100 * 100 - 4 * 4 = 9984 |
| 10) | 105 * 95 = | | 10) 100 * 100 - 5 * 5 = 9975 |
| 11) | 56 * 27 + 27 * 44 = | | 11) ( 56 + 44) * 27 = 2700 |
| 12) | 65 * 86 + 86 * 35 = | | 12) ( 35 + 65) * 86 = 8600 |
| 13) | 22 * 262 - 22 * 62 = | | 13) ( 262 - 62) * 22 = 4400 |
| 14) | 262 * 71 - 62 * 71 = | | 14) ( 262 - 62) * 71 = 14200 |
| 15) | 137 * 60 - 37 * 60 = | | 15) ( 137 - 37) * 60 = 6000 |
| 16) | 88 * 55 + 145 * 88 = | | 16) ( 145 + 55) * 88 = 17600 |
| 17) | 46 * 160 - 60 * 46 = | | 17) ( 160 - 60) * 46 = 4600 |
| 18) | 162 * 63 - 63 * 62 = | | 18) ( 162 - 62) * 63 = 6300 |
| 19) | 47 * 59 + 47 * 41 = | | 19) ( 41 + 59) * 47 = 4700 |
| 20) | 246 * 61 - 46 * 61 = | | 20) ( 246 - 46) * 61 = 12200 |
|
Score: ______________ | |
