Jerry is presently twice as old as his brother and six years older than his sister. How many years from now will Jerry’s age be 2/3 of the combined ages of his brother and sister at that time?
+36916 Jerry's age = x
Brother's age = 1/2x
Sister's age = x -6
y = number of years
x+y = 2/3 (1/2x +y + x-6 +y)
x+y = x + 4/3 y -4
y = 4/3 y - 4
-1/3 y = -4
y = 12 years from now
