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26 votes
26 votes
in a class 60% of the students are girls they are 18 girls in the class how many students are in the class how many boys are in the class

User Henk Mollema
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2.9k points

1 Answer

22 votes
22 votes

Let the number of students in the class be n

Then

60% of n = 18


\begin{gathered} \Rightarrow(60n)/(100)=(18)/(1) \\ \text{cross multiplying, we have} \\ 60n=100*18 \\ \Rightarrow n=(100*18)/(60)=30 \end{gathered}

Therefore there are 30 students in the class

Since there are 18 girls, then there must be (30-18) boys in the class

That is there are 12 boys in the class

User Khanna
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3.1k points