Question discussion

The mean marks of 30 students in a class is 58.5. Later on, it was found that 75 was wrongly recorded as 57. Find the correct mean.

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1
The mean marks of 30 students in a class is 58.5. Later on, it was found that 75 was wrongly recorded as 57. Find the correct mean.
  • A57.1
  • B58.1
  • C59.1
  • D80.1
Correct answer: C

Discussion 1

0
CCommunity
59.1

Correct mean = ( sum of total marks - 57 + 75 ) / 30
= ( 30 x 58.5 - 57 + 75 ) / 30
= (1755 + 18 ) / 30
= 59.1