Three types of rice flour, G, H and J come in containers of 150 g, 200 g and 250 g respectively. Containers of G, H and J are mixed together in the ratio 1 : 2 : 4 to obtain 15.5 kg of an assortment of rice flour.

1. How many containers of G and H are used altogether?
2. Find the difference between the combined weight of all the rice flour in containers H and containers J as compared to the rice flour in containers G. Express the weight in kilograms.

	G	H	J
Number	1 u	2 u	4 u
Value	150	200	250
Total value	150 u	400 u	1000 u

(a)
Total mass of rice flour
= 150 u + 400 u + 1000 u
= 1550 u

1550 u = 15500

1 u = 15500 ÷ 1550 = 10

Total number of containers of G and H used
= 1 u + 2 u
= 3 u
= 3 x 10
= 30 

(b)
Combined weight of all the rice flour in containers H and containers J
= 400 u + 1000 u
= 1400 u

Difference between the combined weight of all the rice flour in containers H and containers J as compared to the rice flour in containers G
= 1400 u - 150 u
= 1250 u
= 1250 x 10
= 12500 g
= 12.5 kg 

Answer(s): (a) 30; (b) 12.5 kg