Explanation:
The score of Sachin in consecutive five innings at 80, 90 ,100, 100 and M respectively.
The average of the five innings is 100.
We need to find the value of M.
Average = sum of observations/total no of observations
Sum of observations = 80+90+100+100+M
= 370 + M
Total no. of observations = 5
Put all the values,
So, he scored 130 in his last innings.
He scored (130-80 = 50) more in his last innings as compared to the first inning scored.