Three types of flour, L, M and N come in containers of 60 g, 150 g and 240 g respectively. Containers of L, M and N are mixed together in the ratio 3 : 6 : 7 to obtain 30.36 kg of an assortment of flour.

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

	L	M	N
Number	3 u	6 u	7 u
Value	60	150	240
Total value	180 u	900 u	1680 u

(a)
Total mass of flour
= 180 u + 900 u + 1680 u
= 2760 u

2760 u = 30360

1 u = 30360 ÷ 2760 = 11

Total number of containers of L and M used
= 3 u + 6 u
= 9 u
= 9 x 11
= 99 

(b)
Combined weight of all the flour in containers M and containers N
= 900 u + 1680 u
= 2580 u

Difference between the combined weight of all the flour in containers M and containers N as compared to the flour in containers L
= 2580 u - 180 u
= 2400 u
= 2400 x 11
= 26400 g
= 26.4 kg 

Answer(s): (a) 99; (b) 26.4 kg