Maths Olympiad - Algebra 2

Question:

If 30% of p is q, and 20% of q is 12, what is 50% of p + q?

Answer:

20% q = 12
100% q = 12 x 5
q = 60

30% p = q
30% p = 60
100% p = 100/30 x 60
p = 200

Therefore, 50% of p + q = 50% (200 + 60)
= 50% (260)
= 130