InterviewSolution
Saved Bookmarks
| 1. |
33. A two digit number is four times the sum of the digits. It is also equal to 3 times the product of digitsA two digit number is four times the sum of the digits. It is also equal to 3 times the productFind the number |
|
Answer» A two digit positive integer can be expressed as 10x+y, where x is the tens digit and y is the ones digit. For example, 37 = 3(10)+7. So, 10x+y = 4(x+y) and 10x+y = 3xy 10x+y = 4x+4y 6x = 3y y = 2x Since y = 2x and 10x+y = 3xy, we have 10x+2x=3x(2x) 12x = 6x26x2-12x = 0 6x(x-2) = 0 x = 0 or x = 2 Since x can't be zero, x = 2 y = 2x = 4 The number is 24. |
|