Question

Frank is 4 times as old as Lin. The difference in their ages is equal to Lin’s age plus 8. How old is each?

Answer 1

Let Lin be x years old.
Lin = x
Frank = 4x

The difference in their ages is equal to Lin’s age plus 8
⇒4x - x= x + 8

Solve x:
4x - x= x + 8

Combine like terms:
3x = x + 8

Take away x from both sides:
2x = 8

Divide by 2 on both sides:
x = 4

Lin is 4 years old.
Frank is 4 x 4 = 16 years old.

Answer: Lin is 4 years old and Frank is 16 years old.

Answer 2

Lets just say Lin's age is 4 so then Franks age would be 16. Lin's age + 8 is 12 and the difference between their ages is 12. That means Lin's age is 4 and Franks age is 16. I guessed a few numbers and went higher or lower and I just found the answer, so I hope this helps!