One number is 3 times as big as another number. If the difference between these two numbers is 60 then what is the larger number?
x = larger number
y = smaller number
x = 3y
x - y = 60
Substitution Method:
3y - y = 60
2y = 60
2y/2 = 60/2
y = 30
Solve for x
x = 3(30)
x = 90
90 - 30 = 60