Answer:
54 years
Step-by-step explanation:
Joyce age = x
Alex age = y
3x = 2y - - - (1)
y - 9 = 2(x - 9)
y - 9 = 2x - 18
-9 + 18 = 2x - y
9 = 2x - y
y = 2x - 9 - - (2)
3x = 2y
3x = 2(2x - 9)
3x = 4x - 18
18 = 4x - 3x
18 = x
Hence,
Mrs stone is 3 * 18 = 54 years