Question Video: Solving Word Problems Involving Sampling and Percentages Mathematics • Second Year of Preparatory School

Video Transcript

A factory produces three different models of cars every year: 673 of the first model, 514 of the second model, and 213 of the third model. If the manager wants to select a sample of 14 percent of all of the cars for inspection, how many cars will be in the sample?

If we would like 14 percent of all of the cars, we need to find the total number of cars. So we need to add 673 from the first model plus 514 from the second model and 213 from the third model. This means there’re 1400 total cars. If we need to find 14 percent of the total, we need to take 14 percent times the total.

So we need 14 percent times 1400. 14 percent can be written as a decimal; we just need to take 14 divided by 100 and get rid of the percentage sign. 0.14 times 1400 equals 196. This must mean that there are 196 cars that will be in the sample for inspection.