Three types of bread flour, M, N and P come in containers of 180 g, 360 g and 420 g respectively. Containers of M, N and P are mixed together in the ratio 2 : 4 : 5 to obtain 35.1 kg of an assortment of bread flour.

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

	M	N	P
Number	2 u	4 u	5 u
Value	180	360	420
Total value	360 u	1440 u	2100 u

(a)
Total mass of bread flour
= 360 u + 1440 u + 2100 u
= 3900 u

3900 u = 35100

1 u = 35100 ÷ 3900 = 9

Total number of containers of M and N used
= 2 u + 4 u
= 6 u
= 6 x 9
= 54 

(b)
Combined weight of all the bread flour in containers N and containers P
= 1440 u + 2100 u
= 3540 u

Difference between the combined weight of all the bread flour in containers N and containers P as compared to the bread flour in containers M
= 3540 u - 360 u
= 3180 u
= 3180 x 9
= 28620 g
= 28.62 kg 

Answer(s): (a) 54; (b) 28.62 kg