Ethan, Charlie and Glen had some stamps in the ratio of 2 : 3 : 5. Glen gave 40% of his stamps to Ethan and Charlie. As a result, Ethan had the same number of stamps as Charlie and Glen had 26 fewer stamps than Ethan.

1. What was the percentage increase in Ethan's stamps after receiving from Glen?
2. How many stamps did Charlie have at first?

Ethan	Charlie	Glen	Total
2 u	3 u	5 u	10 u
+ 2 u		- 2 u
3.5 u	3.5 u	3 u	10 u

(a)
Number of stamps that Glen gave away
= 40% x 5
= ⁴⁰₁₀₀ x 5
= 2 u

Number of stamps that Ethan and Charlie each had in the end
= (10 u - 3 u) ÷ 2
= 7 u ÷ 2
= 3.5 u

Increase in the number of stamps that Ethan had
= 3.5 u - 2 u
= 1.5 u

Percentage increase in Ethan's stamps after receiving from Glen
= ^1.5₂ x 100%
= 75%

(b)
3.5 u = 3 u + 26
3.5 u - 3 u = 26
0.5 u = 26

1 u = 26 ÷ 0.5 = 52

Number of stamps that Charlie had at first
= 3 u
= 3 x 52
= 156

Answer(s): (a) 75%; (b) 156