The average of runs scored by a cricketer in his 99 innings is 99. How many runs will he have to score to his 100th innings so that his average of runs in 100 innings will become 100 ?

Answer: Option C

99 × 99 + k = 100 × 100
k = 199

Alternate :
In 100^th innings average increased by 1
Runs scored in 100^th innings
= 100 × 1 + 99 = 199