Sports Day 2

There are 15 boys in the class. 3 boys and 2 girls did not participate in the sports day. How many girls are there in the class if 80% of the students in the class participated in the sports day?

Final Answer:

d =  10

Step-by-step explanation:

$$\begin{gathered} c=15 \\ p=80\%=\frac{80}{100}=\frac{4}{5}=0.8 \\ {p}_2=1-p=1-0.8=\frac{1}{5}=0.2 \\ 20\%\dots .5deti \\ n=5/p_2=5/0.2=25 \\ c+d=n \\ d=n-c=25-15=10 \\ \text{ Verifying Solution: } \\ P=100\cdot \frac{c+d-3-2}{c+d}=100\cdot \frac{15+10-3-2}{15+10}=80\% \end{gathered}$$

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