Archie had 275 coins. ³₅ were green and the rest were pink and brown. The ratio of the number of pink coins to the number of brown coins was 1 : 4. Archie decided to give away some green coins to decrease the number of green coins to half of the total number of coins.

1. How many more green coins than pink coins did he have at first?
2. How many green coins did he have to give away?

Green coins	Pink coins	Brown coins	Total
3x5	2x5
	1x2	4x2
15 u	2 u	8 u	275

	Green coins	Pink coins	Brown coins
Before	15 u	2 u	8 u
Change	- ?
After	10 u	10 u
Comparing green, pink and brown coins in the end	1	1

(a)
The total number of pink coins and brown coins is repeated. Make the total number of pink coins and brown coins the same.  LCM of 2 and 5 is 10.

Total number of coins at first
= 15 u + 2 u + 8 u
= 25 u

25 u = 275

1 u = 275 ÷ 25 = 11

Number of more green coins than pink coins at first
= 15 u - 2 u
= 13 u
= 13 x 11
= 143

(b)
Number of more green coins that Archie had to give away
= 15 u - 10 u
= 5 u
= 5 x 11
= 55

Answer(s): (a) 143; (b) 55