Question

The average runs scored by Naresh in four matches is $48$. In the fifth match, Naresh scores some runs such that his average now becomes $60$. In the sixth match, he scores $12$ runs more than his fifth match and now the average of his last five matches becomes $78$. Then the runs scored in his first match is (He does not remain not out in any of the match)

• A. $70$
• B. $30$
• C. $45$
• D. $20$

Answer 1

The correct option is B $30$

According to given data, runs scored by Naresh in first $4$ matches $=48\times 4=192$
Average of $5$ matches is $60$, so total runs scored after $5$ matches $=60\times 5=300$
$\Rightarrow$ Score of $5$th match $=300-192=108$
Now in $6$th match, he scores $12$ runs more than this, so, he scored $120$ in the $6$th match.
Hence total runs scored in $6$ matches $=300+120=420$

Now average of last five matches is $78$, so runs scored in last $5$ matches $=78\times 5=390$
$\therefore$ Runs scored in first match $=420-390=30$