Explanation:

- Initially, the cricketer has played 20 innings with an average of 48. Therefore, the total runs scored in these 20 innings is 20 × 48 = 960 runs.

- He scores an additional 240 runs in the subsequent innings.

- His total runs after these further innings: 960 + 240 = 1200 runs.

- His average after these innings is 40, so the equation becomes 1200 runs = 40 × total innings.

- Solving this gives total innings = 1200 ÷ 40 = 30 innings.

- So, the total number of innings he played is 30.

- Option 1: 28 – Incorrect, as calculations show total innings are 30.

- Option 2: 26 – Incorrect, below the calculated innings.

- Option 3: 29 – Incorrect, slightly less than the correct number.

- Option 4: 30 – Correct, matches calculated innings.

- Option 5: 27 – Incorrect, below the accurate count.