8 out of 10 students have to take a course

Question

About 8 out of 10 students need to take a refresher math course. If there are 1000 students how many will probably need to take the refresher course

Answer 1

8 divided by 10 will give you a percentage of students that will need to take the refresher math course.  In this case, 8/10 = 0.8 which, when converted to a percent, is 80%. This means that 80% of students will need a refresher course.  This ratio and percentage will apply to the larger number as well.  In order to apply this percentage to the larger number, we will take 1000 and multiply it times the decimal version of the percent (0.8) in order to find out how many out of 1000 students will need a refresher course.  The answer comes out to 800.

 

Setup:

8/10 = x/1000 

Cross Multiply:

8*1000 = 10*x ---------->  8000 = 10x

 

Divide both sides by 10:

8000/10 = 10x/10 -------------> 800 = x