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In a certain school, 20% of students are below 8 years of age. The number of students above 8 years of age is 2/3 of the number of students of 8 years of age which is 48. What is the total number of students in the school?

172
280
3120
4150

Answer:- 4

Explanation:-

Solution:

Let the number of students be x. Then,
Number of students above 8 years of age

\begin{aligned} = (100 - 20) % of x = 80 % of x . \\ ∴ 80 % of x = 48 + \frac{2}{3} of 48 \\ \Rightarrow \frac{80}{100} x = 80 \\ \Rightarrow x = 100. \end{aligned}

$\eqalign{ & = \left( {100 - 20} \right)\% \,{\text{of}}\,x = 80\% \,{\text{of}}\,x. \cr & \therefore 80\% \,{\text{of}}\,x = 48 + \frac{2}{3}\,{\text{of}}\,48 \cr & \Rightarrow \frac{{80}}{{100}}x = 80 \cr & \Rightarrow x = 100. \cr}$

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", "dateCreated": "7/24/2019 10:09:12 AM", "author": { "@type": "Person", "name": "Nitin Sir" } }, "suggestedAnswer": { "@type": "Answer", "text": "

Solution:

Let the number of students be x. Then,
Number of students above 8 years of age

\begin{aligned} = (100 - 20) % of x = 80 % of x . \\ ∴ 80 % of x = 48 + \frac{2}{3} of 48 \\ \Rightarrow \frac{80}{100} x = 80 \\ \Rightarrow x = 100. \end{aligned}

$\eqalign{ & = \left( {100 - 20} \right)\% \,{\text{of}}\,x = 80\% \,{\text{of}}\,x. \cr & \therefore 80\% \,{\text{of}}\,x = 48 + \frac{2}{3}\,{\text{of}}\,48 \cr & \Rightarrow \frac{{80}}{{100}}x = 80 \cr & \Rightarrow x = 100. \cr}$ ", "dateCreated": "7/24/2019 10:09:12 AM" } }

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