SOLUTION: out of a class of 40 student 25% are girls.how many boys are in the class

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Question 717573: out of a class of 40 student 25% are girls.how many boys are in the class
Answer by jndarrell(58) About Me  (Show Source):
You can put this solution on YOUR website!
Since they give you the percent of girls, find that first. Then take the difference of the number of girls and the entire class and that answer will be the number of boys. See below:
x over 40 = 25 over 100
Cross multiply
100x=1000
Divide both sides by 100 to get x alone
x=10
There are 10 girls in a class of 40 students. 40-10=30
There are 30 boys in the class. To check this result you can do 30/40=75/100. The 30 boys should equate to the other 75% of students.
:)