Xandra had four containers, K, L, M and N which contained a total of 236 lemons. She transferred 10 lemons from Container K to Container L, 36 lemons from Container L to Container M and 60 lemons from Container M to Container N. The ratio of the number of lemons in Container K to Container L to Container M changed from  2 : 7 : 9 to 1 : 5 : 8. How many lemons were in Container N at first?

	Make p the same (1)x5 = (3)	K (1)	L (2)	M	N
Before	10 u	2 u	7 u	9 u	?
Change 1	- 50	- 10	+ 10
Change 2			- 36	+ 36
Change 3				- 60	+ 60
After	5 p	1 p	5 p	8 p	?

2 u - 10 = 1 p --- (1)

7 u + 10 - 36 = 5 p
7 u - 26 = 5 p --- (2)

(1) _{x 5}
10 u - 50 = 5 p --- (3)

Make p the same.

(3) = (2)
10 u - 50 = 7 u - 26
10 u - 7 u = 50 - 26
3 u = 24

1 u = 24 ÷ 3 = 8

Total number of lemons in Container K, Container L and Container M
= 2 u + 7 u + 9 u
= 18 u

Total number of lemons in Container N at first
= 236 - 18 u
= 236 - 18 x 8
= 236 - 144
= 92

Answer(s): 92