Home
Class 9
MATHS
Find the arithmetic mean of:...

Find the arithmetic mean of:

A

21

B

21.4

C

22.75

D

21.75

Text Solution

Verified by Experts

The correct Answer is:
D
`sum_(i=1)^(5)f_(i)x_(i) = f_(1)x_(1) + f_(2)x_(2) + f_(3)x_(3) + f_(4)x_(4) + f_(5)x_(5)`
` = 3 xx 10+4 xx 15 + 2 xx 20 + 5 xx 25 + 6 xx 30`
`=435`
`sum f_(i) = 3+4+2+5+6 = 20`
`"Mean" = (sum f_(i)x_(i))/(sum f_(i)) = (435)/(20) = 21.75`
Promotional Banner

Topper's Solved these Questions

  • STATISTICS

    NAGEEN PRAKASHAN|Exercise Problems From NCERT/exemplar|22 Videos

  • STATISTICS

    NAGEEN PRAKASHAN|Exercise Exercise 14a|10 Videos

  • QUADRILATERALS

    NAGEEN PRAKASHAN|Exercise Revision Exercise (long Answer Questions)|5 Videos

  • SURFACE AREA AND VOLUME

    NAGEEN PRAKASHAN|Exercise Revision Exercise (long Answer Questions)|10 Videos

Similar Questions

Explore conceptually related problems

Find the arithmetic means of first 6 natural numbers.

Find the arithmetic mean from the following distribution. :

Find the arithmetic mean by (a) assumed mean and (b) step deviation mthods.

The following table gives the daily income of ten workers in a factory. Find the arithmetic mean. {:("Workers",A,B,C,D,E,F,G,H,I,J),("Daily Income(in Rs.)",120,150,180,200,250,300,220,350,370,260):}

Find out the arithmetic mean from the following data: {:("Marks (less than)"," "5,10,15,20,25,30),("Number of Students",22310,23,30,54,69,80):}

If x, y, z are in arithmetic progression and a is the arithmetic mean of x and y and b is the arithmetic mean of y and z, then prove that y is the arithmetic mean of a and b.

Find three arithmetic means between 6 and -6