Three types of flour, X, Y and Z come in containers of 80 g, 200 g and 240 g respectively. Containers of X, Y and Z are mixed together in the ratio 1 : 3 : 4 to obtain 16.4 kg of an assortment of flour.

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

	X	Y	Z
Number	1 u	3 u	4 u
Value	80	200	240
Total value	80 u	600 u	960 u

(a)
Total mass of flour
= 80 u + 600 u + 960 u
= 1640 u

1640 u = 16400

1 u = 16400 ÷ 1640 = 10

Total number of containers of X and Y used
= 1 u + 3 u
= 4 u
= 4 x 10
= 40 

(b)
Combined weight of all the flour in containers Y and containers Z
= 600 u + 960 u
= 1560 u

Difference between the combined weight of all the flour in containers Y and containers Z as compared to the flour in containers X
= 1560 u - 80 u
= 1480 u
= 1480 x 10
= 14800 g
= 14.8 kg 

Answer(s): (a) 40; (b) 14.8 kg