Three types of sugar, K, L and M come in containers of 100 g, 150 g and 300 g respectively. Containers of K, L and M are mixed together in the ratio 1 : 2 : 3 to obtain 7.8 kg of an assortment of sugar.

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

	K	L	M
Number	1 u	2 u	3 u
Value	100	150	300
Total value	100 u	300 u	900 u

(a)
Total mass of sugar
= 100 u + 300 u + 900 u
= 1300 u

1300 u = 7800

1 u = 7800 ÷ 1300 = 6

Total number of containers of K and L used
= 1 u + 2 u
= 3 u
= 3 x 6
= 18 

(b)
Combined weight of all the sugar in containers L and containers M
= 300 u + 900 u
= 1200 u

Difference between the combined weight of all the sugar in containers L and containers M as compared to the sugar in containers K
= 1200 u - 100 u
= 1100 u
= 1100 x 6
= 6600 g
= 6.6 kg 

Answer(s): (a) 18; (b) 6.6 kg