The average score (runs/match) of Mithali before the start of the women’s national series was 45. In the women’s national series of 10 matches, her total score was 500 runs. Find the total number of matches played by her till date, if her new average after the series is 47.5.
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 10.
Let the number of matches played by Mithali before the series be x
Then the sum of her scores in x matches = 45x
After 10 more innings, her total score becomes (45x + 500) in (x + 10) matches
Her new average score = 47.5
⇒ (45x + 500)/(x + 10) = 47.5
⇒ 45x + 500 = 47.5x + 475
⇒ 2.5x = 25 ⇒ x = 10