Frequency distribution date is given below. If average age is 17, years, value of m is Age Age (in y

English

Gujarati

Hindi

4.Average

hard

The frequency distribution date is given below. If the average age is $17\, years,$ the value of $m$ is Age

Age (in $years$) : 8 20 26 29

Number of People : 3 2 m 1

A

$1$

B

$2$

C

$3$

D

$4$

Solution

Required average

$=\frac{8 \times 3+20 \times 2+26 \times m+29 \times 1}{3+2+m+1}$

$\Rightarrow 17=\frac{24+40+26 m+29}{6+m}$

$\Rightarrow 17(6+m)=93+26 m$

$\Rightarrow 102+17 m)=93+26 m$

$\Rightarrow 26 m-17 m=102-93$

$\Rightarrow 9 m=9 \Rightarrow m=1$

Standard 13

Quantitative Aptitude

Share

Similar Questions

The average score of Sachin after $25$ innings is $46$ runs per innings. If after the $26^{th}$ innings, his average runs increased by $2$ runs, then what is his score in the $26^{\text {th }}$ innings?

easy

The average weight of a group of $20 \,boys$ was calculated to be $89.4\, kg$ and it was later discovered that one weight was misread as $78 \,kg$ instead of $87 \,kg.$ The correct average weight is (in $kg.$)

easy

The average of $25$ results is $20 .$ the average of first $12$ results is $15$ and that of the last $12$ results is $18 .$ Then, the $13^{ th}$ results is

medium

Three $years$ ago the average age of a family of $5$ members was $17\, years.$ With the birth of a new baby, the average remains the same three even today. Find out the age of the baby.(in $years$)

medium

The average weight of $3 \operatorname{men} A, B$ and $C$ is $84\, kg.$ Another man $D$ joins the group and the average now becomes $80 \,kg .$ If another man $E ,$ whose weight is $3 \,kg$ more than that of $D ,$ replaces $A,$ then the average weight of $B, C, D$ and $E$ becomes $79 \,kg .$ The weight of $A$ is (in $kg$)

hard