In April, Linda and Luis had stamps in the ratio 5 : 2. In May, each of them gave away the same number of stamps. Linda then had five times as many stamps as Luis.

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

	Linda	Luis	Difference
Before	5x4 = 20 u	2x4 = 8 u	3x4 = 12 u
Change	- 5 u	- 5 u
After	5x3 = 15 u	1x3 = 3 u	4x3 = 12 u

(a)
Since Linda and Luis gave away the same number of stamps, the difference in the number of stamps between Linda and Luis at first and in the end remains the same.

Make the difference in the number of stamps at first and in the end the same. LCM of 3 and 4 is 12.

Luis's stamps in April : Luis's stamps in May
8 : 3

(b)
Total number of stamps in April
= 20 u + 8 u
= 28 u

Total number of stamps in May
= 15 u + 3 u
= 18 u

Total stamps in April : Total stamps in May
28 : 18 _(÷2)
14 : 9 

Answer(s): (a) 8 : 3; (b) 14 : 9