Multiple choice

The average marks of 50 students were found to be 40. Later on, it was discovered that a score of 53 was misread as 83. Find the correct average corresponding to the correct score. 50 छात्रों के औसत अंक 40 थे। बाद में पता चला कि एक छात्र के 53 अंकों को गलती से 83 पढ़ लिया गया था। सही अंकों के साथ सही औसत होगा ।

  1. 39.4

  2. 38.9

  3. 38.7

  4. 39
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Original sum = 50 × 40 = 2000. Correct sum = 2000 - 83 + 53 = 1970. Correct average = 1970 ÷ 50 = 39.4. The error was counting 30 extra points (83 - 53), which reduced average by 30/50 = 0.6.

Keep practicing — related questions