hello!
to solve this equation, you have to find the percentage of defects out of the total amount of jeans. if there are 300 pairs of jeans with 8 faulty pairs, then the percentage of defects would be 2.666(etc). 2.666(etc) percent of 3000 is roughly 80 pairs of defective jeans.
therefore your final answer would be 80 pairs of jeans!