Question

1. Set up the following word problem as a proportion and solve.

Then write your answer as a complete sentence. In a random sample of 200 cars of a particular model, 3 have a manufacturing defect. At this rate, how many of 10,000 cars of the same model will have a manufacturing defect?

Answer 1

We expect 150 defects out of the 10,000 cars if the 3 defects out of the 200 cars sampled is representative of all 10,000 cars. First, let's set up the proportions. We have 3/200 cars with defects and we want to know X for X/10000. So 3/200 = X/10000 Now solve for X. 3/200 = X/10000 10000*3/200 = 10000 * X/10000 30000/200 = X 150 = X So the answer is: We expect 150 defects out of the 10,000 cars if the 3 defects out of the 200 cars sampled is representative of all 10,000 cars.