Lee had three bags of potato starch, J, K and L and the mass of each bag of potato starch was in the ratio 4 : 3 : 1. Lee decided to transfer 40% of potato starch from Bag J into Bag K and 70% of potato starch from Bag L into Bag K. Given that the mass of Bag K was 26.5 kg in the end, how many kilograms of potato starch were transferred into Bag K?

	J	K	L
Before	4 u	3 u	1 u
Change 1	- 1.6 u	+ 1.6 u
Change 2		+ 0.7 u	- 0.7 u
After	2.4 u	5.3 u	0.3 u

Mass of potato starch transferred from Bag J into Bag K
= 40% x 4 u
= ⁴⁰₁₀₀ x 4 u
= 2.4 u

Mass of potato starch transferred from Bag L into Bag K
= 70% x 1 u
= ⁷⁰₁₀₀ x 1 u
= 0.7 u

Mass of potato starch in Bag K in the end
= 3 u + 1.6 u + 0.7 u
= 5.3 u

5.3 u = 26.5 

1 u = 26.5 ÷ 5.3 = 5

Mass of potato starch transferred into Bag K
= 1.6 u + 0.7 u
= 2.3 u
= 2.3 x 5
= 11.5 kg

Answer(s): 11.5 kg