Lucy is 3 times Linus's age. If the difference in their age is 8 years, how old is Lucy?

Question

Lucy is 3 times Linus's age. If the difference in their age is 8 years, how old is Lucy?  Can you please show me how to get the answer

Answer 1

Let X be Linus' age.  Then Lucy's age is 3X and 3X - X = 8.  

 

3X - X = 8

 

2X = 8

 

X = 4 (Linus)

 

3X = 12 (Lucy)