Question

A man whose bowling average is $12.4$ takes $5$ wickets for $26$ runs and thereby decreases his average by $0.4$. What is the number of wickets taken by him before his last match?

Answer 1

Let the number of wickets taken by him before the match be $x$.

The bowling average is given to be $12.4$.

Total runs $=12.4x$

The runs scored including this match is given by $12.4x+26$ with the average of $12$.

$$\begin{gathered} \frac{(12.4x+26)}{x+5}=12 \\ 12.4x+26=12x+60 \\ 12.4x-12x=60-26 \\ 0.4x=34 \\ \therefore x=85wickets \end{gathered}$$

Hence, $85$ wickets are taken by the man before his last match.