Three types of rice flour, Q, R and S come in containers of 120 g, 150 g and 240 g respectively. Containers of Q, R and S are mixed together in the ratio 3 : 5 : 6 to obtain 15.3 kg of an assortment of rice flour.

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

	Q	R	S
Number	3 u	5 u	6 u
Value	120	150	240
Total value	360 u	750 u	1440 u

(a)
Total mass of rice flour
= 360 u + 750 u + 1440 u
= 2550 u

2550 u = 15300

1 u = 15300 ÷ 2550 = 6

Total number of containers of Q and R used
= 3 u + 5 u
= 8 u
= 8 x 6
= 48 

(b)
Combined weight of all the rice flour in containers R and containers S
= 750 u + 1440 u
= 2190 u

Difference between the combined weight of all the rice flour in containers R and containers S as compared to the rice flour in containers Q
= 2190 u - 360 u
= 1830 u
= 1830 x 6
= 10980 g
= 10.98 kg 

Answer(s): (a) 48; (b) 10.98 kg