Question 257695
Hello, 
Let's set up "x" as the total number of students. So now we can set up an equation:
40%x+15=x rewritten as:
.4x+15=x Subtract .4x from both sides will give us:
15=.6x  Now divide each side by .6 to be:
25=x  Therefore we know there are 25 students in the class. 
Make sense?
RJ
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