Jeremy had three bags of barley, J, K and L and the mass of each bag of barley was in the ratio 1 : 4 : 4. Jeremy decided to transfer 40% of barley from Bag J into Bag K and 80% of barley from Bag L into Bag K. Given that the mass of Bag K was 45.6 kg in the end, how many kilograms of barley were transferred into Bag K?

	J	K	L
Before	1 u	4 u	4 u
Change 1	- 0.4 u	+ 0.4 u
Change 2		+ 3.2 u	- 3.2 u
After	0.6 u	7.6 u	0.8 u

Mass of barley transferred from Bag J into Bag K
= 40% x 1 u
= ⁴⁰₁₀₀ x 1 u
= 0.6 u

Mass of barley transferred from Bag L into Bag K
= 80% x 4 u
= ⁸⁰₁₀₀ x 4 u
= 3.2 u

Mass of barley in Bag K in the end
= 4 u + 0.4 u + 3.2 u
= 7.6 u

7.6 u = 45.6 

1 u = 45.6 ÷ 7.6 = 6

Mass of barley transferred into Bag K
= 0.4 u + 3.2 u
= 3.6 u
= 3.6 x 6
= 21.6 kg

Answer(s): 21.6 kg