Question 507864
Let
Present age of Joe = j
Present age of Mack = m
Given
Joe is 3 times as old as Mack
j=3m ........(1)
The difference in their age is 24
j-m=24
Put the value of j in above equation we have
3m-m=24
2m=24
Divide by m both sides of the equation
2m/2=24/2
m=12

Put the value of m in (1)
j=3m
j=3(12)
j=36
Present age of Joe = 36 years old
Present age of Mack = 12 years old