A batsman's average score for a certain number of innings is 44. If he scores 132 runs in the next innings, his average becomes 4…

Question

A batsman's average score for a certain number of innings is 44. If he scores 132 runs in the next innings, his average becomes 48. How many innings did he play earlier?

1. A. 21 (Correct answer)
2. B. 22
3. C. 23
4. D. 24

Correct Answer

Option A — 21

Detailed Solution & Explanation

The correct answer is 21.

Key Points

• Let the earlier number of innings be n, so the runs then totalled 44n.
• After one more innings of 132 runs, the average over (n + 1) innings is 48:
  • 44n + 132 = 48(n + 1)
  • 44n + 132 = 48n + 48
  • 84 = 4n → n = 21
• He had played 21 innings earlier.

Additional Information

• A shortcut: the new innings must lift every earlier innings by 4 runs and also supply the new average. Excess = 132 − 48 = 84, and 84 ÷ 4 = 21.
• The general result is n = (new score − new average) ÷ (increase in average).
• Check: 21 × 44 = 924, plus 132 = 1,056, over 22 innings = 48 ✓ — a five-second verification worth doing every time.

प्रश्न (हिन्दी में)

एक बल्लेबाज का निश्चित संख्या में पारियों का औसत स्कोर 44 है। यदि वह अगली पारी में 132 रन बनाता है, तो उसका औसत 48 हो जाता है। उसने पहले कितनी पारियाँ खेली थीं?

1. A. 21
2. B. 22
3. C. 23
4. D. 24