Question

The sum of three numbers is 69. If the second number is equal to the first diminished by 8, and the third number is 5 times the first. What are the numbers?

If x represents the first number, then which of the following equations could be used to solve the problem?

69 = 7x - 8
x = 6x - 8
69 = 6x - 8

Answer 1

`69 = 6x - 8`

Explanation:

All 3 numbers must sum to 69, so we can draw out the second option
`x = 6x - 8`

Let the first number be x, adding 5x to the first x would give you 6x for the sum of the first and third numbers, therefore you can remove
`69 = 7x - 8` from your considerations as it includes 7x not 6x.

This leaves you with the one final answer
`69 = 6x - 8`