In March, Shiyun and Oscar had marbles in the ratio 15 : 8. In April, each of them gave away the same number of marbles. Shiyun then had five times as many marbles as Oscar.

1. Find the ratio of the number of marbles Oscar had in March to the number of marbles he had in April.
2. Find the ratio of the total number of marbles both had in March to the total number of marbles both had in April.

	Shiyun	Oscar	Difference
Before	15x4 = 60 u	8x4 = 32 u	7x4 = 28 u
Change	- 25 u	- 25 u
After	5x7 = 35 u	1x7 = 7 u	4x7 = 28 u

(a)
Since Shiyun and Oscar gave away the same number of marbles, the difference in the number of marbles between Shiyun and Oscar at first and in the end remains the same.

Make the difference in the number of marbles at first and in the end the same. LCM of 7 and 4 is 28.

Oscar's marbles in March : Oscar's marbles in April
32 : 7

(b)
Total number of marbles in March
= 60 u + 32 u
= 92 u

Total number of marbles in April
= 35 u + 7 u
= 42 u

Total marbles in March : Total marbles in April
92 : 42 _(÷2)
46 : 21 

Answer(s): (a) 32 : 7; (b) 46 : 21