If p : q = 3 : 2, find ratio (4p + 5q) : (4p - 5q).

Question: If p : q = 3 : 2, find ratio (4p + 5q) : (4p - 5q).

Solution:
(4p + 5q) : (4p - 5q)
= q(4p/q + 5) : q(4p/q - 5)
= (4 × 3/2 + 5) : (4 × 3/2 - 5)
= (6 + 5) : (6 - 5)
= 11 : 1