In April, Kylie and Perry had marbles in the ratio 11 : 7. In May, each of them gave away the same number of marbles. Kylie then had twice as many marbles as Perry.

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

	Kylie	Perry	Difference
Before	11x1 = 11 u	7x1 = 7 u	4x1 = 4 u
Change	- 3 u	- 3 u
After	2x4 = 8 u	1x4 = 4 u	1x4 = 4 u

(a)
Since Kylie and Perry gave away the same number of marbles, the difference in the number of marbles between Kylie and Perry 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 4 and 1 is 4.

Perry's marbles in April : Perry's marbles in May
7 : 4

(b)
Total number of marbles in April
= 11 u + 7 u
= 18 u

Total number of marbles in May
= 8 u + 4 u
= 12 u

Total marbles in April : Total marbles in May
18 : 12 _(÷6)
3 : 2 

Answer(s): (a) 7 : 4; (b) 3 : 2