Each of the products produced yesterday was checked by worker x or worker y. 0.5% of the products checked by worker x are defective and 0.8% of the products checked by worker y are defective. If the total defective rate of all the products checked by worker x and worker y is 0.65%, what fraction of the products was checked by worker y?
Choose the correct choice from the following:
A) 1/5
B) 1/2
C) 2/3
D) 1/4
E) 2/5
x: 0.5% is 0.15%-points from 0.65%.   y: 0.8% is 0.15%-points from 0.65%.   Therefore the ratio of products checked by y:x is 1:1.   Thus, worker y checked 1/2 of the products.   The answer is 1/2.
<result>B</result>
Each of the products produced yesterday was checked by worker x or worker y. 0.5% of the products checked by worker x are defective and 0.8% of the products checked by worker y are defective. If the total defective rate of all the products checked by worker x and worker y is 0.65%, what fraction of the products was checked by worker y?