Question

Average run scored by a batsman in his 14 innings was x. In his 15^th inning he score 100 runs and average score increased by 5 runs. Find the new average of the batsman.
1. 20
2. 25
3. 30
4. 35

Answer 1

Correct Answer - Option 3 : 30

Given:

Average score in 14 innings = x

Total run scored in 15^th inning = 100

After the 15^th inning average increased by 5

Formula used:

Average = Sum of observation/Number of observation

Calculation:

According to the formula, we have

Average of 14 innings = (Total runs scored in 14 innings)/14

⇒ (Total runs scored in 14 innings)/14 = x

⇒ Total runs scored in 14 innings = 14x      ---(1)

According to the question, we have

Average of 15 innings = Average of 14 innings + 5

⇒ (Total runs scored in 15 innings)/15 = x + 5

⇒ Total runs scored in 14 innings + 100 = 15x + (5 × 15)      ---(2)

Put value of equation (1) in equation (2), we get

⇒ 14x + 100 = 15x + 75

⇒ 15x - 14x = 100 - 75

⇒ x = 25

So, new average = x + 5

⇒ 25 + 5

⇒ 30

∴ The new average of batsman is 30.