Question

A factory manager conducted tests on a random sample of 150 products.of the products tested 2 were found to have defects.Based on this information how many products in a batch of 3000 are likely to be defective

Answer 1

The best information we can use is the ratio of defectuosity, 2/150
Applying it to the size of the batch
N=3000*2/150 = 40
Answer: out of the batch of 3000 products, likely 40 products are defective, if the products are drawn from the same production run.