Question 961000
Nadia is 69 years old and Kevin is 9 years old.
How many years will it take until Nadia is only 4 times as old as Kevin?
:
Let y = the no. of years for this to be true
:
69 + y = 4(9 + y)
69 + y = 36 + 4y
69 - 36 = 4y - y
33 = 3y 
y = 33/3
y = 11 yrs from now N will be 4 times K's age
:
:
see if this is true
69 + 11 = 4(9 + 11)
80 = 4(20)