Three types of sugar, L, M and N come in containers of 120 g, 240 g and 360 g respectively. Containers of L, M and N are mixed together in the ratio 2 : 3 : 5 to obtain 13.8 kg of an assortment of sugar.

1. How many containers of L and M are used altogether?
2. Find the difference between the combined weight of all the sugar in containers M and containers N as compared to the sugar in containers L. Express the weight in kilograms.

	L	M	N
Number	2 u	3 u	5 u
Value	120	240	360
Total value	240 u	720 u	1800 u

(a)
Total mass of sugar
= 240 u + 720 u + 1800 u
= 2760 u

2760 u = 13800

1 u = 13800 ÷ 2760 = 5

Total number of containers of L and M used
= 2 u + 3 u
= 5 u
= 5 x 5
= 25 

(b)
Combined weight of all the sugar in containers M and containers N
= 720 u + 1800 u
= 2520 u

Difference between the combined weight of all the sugar in containers M and containers N as compared to the sugar in containers L
= 2520 u - 240 u
= 2280 u
= 2280 x 5
= 11400 g
= 11.4 kg 

Answer(s): (a) 25; (b) 11.4 kg