Question

In an examination, 15 % students failed and 425 students passed. Find the number of students failed in the examination

Answer 1

total student = x
then 
total passed = 85x/100 = 425
x= 500
total failed = 15% of x
then 
15x500/100 = 75

Answer 2

$\mathfrak{\large{\underline{\underline{Answer :}}}}$

The total marks are 500.

$\mathfrak{\large{\underline{\underline{Step-by-step\: explanation}}}}$

$\textsf{\underline{\underline{Given : }}}$

Students needs = 40% to pass

Rula gets = 185 marks

Fails by = 15 marks

$\textsf{\underline{\underline{To find :}}}$

The total marks

$\textsf{\underline{\underline{Solution : }}}$

$\textsf{Let the Total Marks be as x }$

As Rula failed by 15, the marks she scored when added by 15 makes the passing marks.

★ $\green{\boxed{\green{\boxed{\red{\sf{40\% \: of \: x = 185 + 15}}}}}}$

$\begin{lgathered}\begin{lgathered}\sf{\longrightarrow} \: 40\% \: of \: x = 185 + 15 \\ \\ \sf{\longrightarrow} \: \frac{40}{100} \times x = 185 + 15 \\ \\ \sf{\longrightarrow} \: \frac{40x}{100} = 200 \\ \\ \sf{\longrightarrow} \:40x = 200 \times 100 \\ \\ \sf{\longrightarrow} \:40x = 20000 \\ \\ \sf{\longrightarrow} \:x = \frac{20000}{40} \\ \\ \sf{\longrightarrow} \:x = 500\end{lgathered}\end{lgathered}$

$\textsf{Total Marks = 500 }$

$\therefore\textsf{The total marks are 500. }$

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