One number is 17 less than 7 times another. If the sum is 31 what are the the numbers?

Answer 1

Let's let x represent one of the numbers. To show "17 less than 7 times" , we could write: 7x - 17 for the second number.

Then the sum could be written as: x + (7x -17) = 31

Now solve this equation for x (or one of the numbers) by combining like terms and using inverse operations as follows:

x + (7x -17) = 31

8x - 17 = 31

8x -17 + 17 = 31 + 17

8x = 48

8x/8 = 48/8

x = 6

One of the numbers is 6. The other will be 7*6 -17 = 42 - 17 or 25

Note that 25 + 6 = 31