Bryan, George and Carl had some coins in the ratio of 3 : 4 : 7. Carl gave 50% of his coins to Bryan and George. As a result, Bryan had the same number of coins as George and Carl had 35 fewer coins than Bryan.

1. What was the percentage increase in Bryan's coins after receiving from Carl?
2. How many coins did George have at first?

Bryan	George	Carl	Total
3 u	4 u	7 u	14 u
+ 3.5 u		- 3.5 u
5.25 u	5.25 u	3.5 u	14 u

(a)
Number of coins that Carl gave away
= 50% x 7
= ⁵⁰₁₀₀ x 7
= 3.5 u

Number of coins that Bryan and George each had in the end
= (14 u - 3.5 u) ÷ 2
= 10.5 u ÷ 2
= 5.25 u

Increase in the number of coins that Bryan had
= 5.25 u - 3 u
= 2.25 u

Percentage increase in Bryan's coins after receiving from Carl
= ^2.25₃ x 100%
= 75%

(b)
5.25 u = 3.5 u + 35
5.25 u - 3.5 u = 35
1.75 u = 35

1 u = 35 ÷ 1.75 = 20

Number of coins that George had at first
= 4 u
= 4 x 20
= 80

Answer(s): (a) 75%; (b) 80