What is the total number of candidates at an examination, if 31 ¾ fail, and the number of those who pass exceeds the number of those who fail by 247?

Let the total number of candidates = x Thea. number of passed candidates

=(100-31 )% of x = 69 % of x

Now. 69 % of x-31 % of x = 247 $\Rightarrow$ 38 % of x = 247

$\Rightarrow \frac{38}{100}x=247\Rightarrow x=\frac{247\times 100}{38}=650$