A 60-gram mixture has a ratio of zinc to copper of 2:1. If the ratio is to be changed to 1:2, what quantity of copper needs to be added?
Show answer & explanation
Correct answer: C
Explanation
Given:
Total mixture = 60 g, Ratio (Zn : Cu) = 2 : 1
According to the formula:
Actual quantity = Ratio × k
Zn = 40 g, Cu = 20 g
Let x g of copper be added.
New ratio = 40 : (20 + x) = 1 : 2
40 / (20 + x) = 1 / 2
80 = 20 + x
x = 60 gram