A batsman in his 13th inning makes a score of 85 runs and there by increases his average by five runs. What is his average after 13th innings?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is Option 2 i.e. 25.
Let's old average = x
He scores 85 runs in the 13th inning
According to the questions
Old average × Old number + New number(score) = New average × New Number
⇒ x × 12 + 85 = (x + 5) × 13
⇒ 12x + 85 = 13x + 65
⇒ 13x - 12x = 85 - 65
⇒ x = 20
Then, New Average = (x + 5 = 20 + 5 = 25) = 25