SOLUTION: 2/5 of the students are boys. there are 12 girls. how many students in all?

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Question 475411: 2/5 of the students are boys. there are 12 girls. how many students in all?
Answer by Tatiana_Stebko(1539) About Me  (Show Source):
You can put this solution on YOUR website!
if 2%2F5 of the sudents are boys, then 1-2%2F5=3%2F5 of the students are girls
Have ratio
3%2F5-12
1-x
Equation
%283%2F5%29x=12 multiply by 5
3x=12%2A5
3x=60 divide by 3
x=60%2F3
x=20 students in the group