Three types of flour, W, X and Y come in containers of 60 g, 120 g and 150 g respectively. Containers of W, X and Y are mixed together in the ratio 3 : 4 : 5 to obtain 8.46 kg of an assortment of flour.

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

	W	X	Y
Number	3 u	4 u	5 u
Value	60	120	150
Total value	180 u	480 u	750 u

(a)
Total mass of flour
= 180 u + 480 u + 750 u
= 1410 u

1410 u = 8460

1 u = 8460 ÷ 1410 = 6

Total number of containers of W and X used
= 3 u + 4 u
= 7 u
= 7 x 6
= 42 

(b)
Combined weight of all the flour in containers X and containers Y
= 480 u + 750 u
= 1230 u

Difference between the combined weight of all the flour in containers X and containers Y as compared to the flour in containers W
= 1230 u - 180 u
= 1050 u
= 1050 x 6
= 6300 g
= 6.3 kg 

Answer(s): (a) 42; (b) 6.3 kg