Q. 145.0( 8 Votes )

# The mean of marks scored by 100 students was found to be 40. Later on it was discovered that a score of 53 was misread as 83. Find the correct mean.

Answer :

Mean marks of 100 students = 40

Sum of marks of 100 students = 100 * 40

= 4000

Correct value = 53

Incorrect value = 83

Correct sum = 4000 – 83 + 53

= 3970

Therefore, correct mean =

= 39.7

Rate this question :

How useful is this solution?

We strive to provide quality solutions. Please rate us to serve you better.

PREVIOUSExplain, by taking a suitable example, how the arithmetic mean alters by (i) adding a constant k to each term, (ii) subtracting a constant k from each them, (iii) multiplying each term by a constant k and (iv) dividing each term by a non-zero constant k.NEXTThe traffic police recorded the speed (in km/h) of 10 motorists as 47, 53, 49, 60, 39, 42, 55, 57, 52, 48. Later on an error in recording instrument was found. Find the correct overage speed of the motorists if the instrument recorded 5 km/hr. less in each case.

Related Videos

Applications of Laws of Motion34 mins

What an Atom holds?41 mins

Types of Present Tense55 mins

Building blocks of brain27 mins

Genius Quiz | Laws of Motion38 mins

Quiz | Conservation of Momentum33 mins

Recently facts of 5th state of Matter: Bose Einstein Condensate52 mins

Applications of Newton's First Law of Motion53 mins

Quiz | Become a Master of Conservation of Momentum32 mins

Test your knowledge of Laws of motion44 mins

Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Expertsview all courses

Dedicated counsellor for each student

24X7 Doubt Resolution

Daily Report Card

Detailed Performance Evaluation

RELATED QUESTIONS :

Find the missing frequencies in the following frequency distribution if it is known that the mean of the distribution is 50.

In a frequency distribution, the mild-value of a class is 10 and width of each class is 6. The lower limit of the class is

RS Aggarwal & V Aggarwal - MathematicsFind the median of the following data

92, 35, 67, 85, 72, 81, 56, 51, 42, 69

RD Sharma - Mathematics