In April, Gillian and Japheth had coins in the ratio 12 : 5. In May, each of them gave away the same number of coins. Gillian then had thrice as many coins as Japheth.

1. Find the ratio of the number of coins Japheth had in April to the number of coins he had in May.
2. Find the ratio of the total number of coins both had in April to the total number of coins both had in May.

	Gillian	Japheth	Difference
Before	12x2 = 24 u	5x2 = 10 u	7x2 = 14 u
Change	- 3 u	- 3 u
After	3x7 = 21 u	1x7 = 7 u	2x7 = 14 u

(a)
Since Gillian and Japheth gave away the same number of coins, the difference in the number of coins between Gillian and Japheth at first and in the end remains the same.

Make the difference in the number of coins at first and in the end the same. LCM of 7 and 2 is 14.

Japheth's coins in April : Japheth's coins in May
10 : 7

(b)
Total number of coins in April
= 24 u + 10 u
= 34 u

Total number of coins in May
= 21 u + 7 u
= 28 u

Total coins in April : Total coins in May
34 : 28 _(÷2)
17 : 14 

Answer(s): (a) 10 : 7; (b) 17 : 14