SOLUTION: In a gym class, the ratio of girls to the total number of students is 3:8 . There are 10 boys in the gym class. How many students are in the gym?

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Question 797513: In a gym class, the ratio of girls to the total number of students is 3:8 . There are 10 boys in the gym class. How many students are in the gym?
Answer by jerryguo41(197) About Me  (Show Source):
You can put this solution on YOUR website!
Proportions can be written as fractions
%28Total+Number+of+Girls%29%2F%28Total+Number+of+Students%29=%283%2F8%29
But you only have number of boys, so you can find the proportion of boys in class by subtracting 1-%283%2F8%29. This means the ratio of boys to students is 5%2F8. Since you can only have boys or girls the remainder of the class must be boys which is why 1-%283%2F8%29 is true.
%28Total+Number+of+Boys%29%2F%28Total+Number+of+Students%29=%285%2F8%29
10%2F%28Total+Number+of+Students%29=%285%2F8%29
80=5%28Total+Number+of+Students%29
Total+Number+of+Students=16