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 0.55%, what fraction of the products was checked by worker y?
Choose the correct choice from the following answers.
A) 1/3 B) 1/4 C) 1/5 D) 1/6 E) 1/8
x: 0.5% is 0.05%-points from 0.55%.   y: 0.8% is 0.25%-points from 0.55%.   Therefore the ratio of products checked by y:x is 1:5.   Thus, worker y checked 1/6 of the products.   The answer is 1/6.
<result>D</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 0.55%, what fraction of the products was checked by worker y?