Question

English

Gujarati

Hindi

4.Average

medium

The average age of a graph of $9$ students is $20\, years.$ When $6$ more students joined the group, the average age falls by $2\, years.$ Then the average age of new students is

$20$

$18$

$19$

$15$

Solution

Average age of new student $=$

$\frac{Old\, Number \,of \,student \,\times \,Old\, average \,of \,students \,- \,New \,average \,\times \,New \,number\, of \,students}{Number \,of \,New \,students}$

$=\frac{9 \times 20-18 \times 15}{6}=\frac{180-270}{6}=\frac{90}{6}=15$ years

Std 13

Quantitative Aptitude

The average marks obtained by $180$ students in an examination is $50 .$ If the average marks of passed students is $40 .$ Then what is the number of students who failed the examination ?

medium

Refer to the line graph and answer the giten question.

Number of candidates who qualified in a given competitite examination from $6$ states during two given $years$

What is the average number of candidates who qualified in the given competitive exam from states $Q,$ $S , T$ and $U$ in $2004 ?$

medium

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

hard

In a coconut grove, $(x+2)$ trees yield $60$ $nuts$ per $year,$ $x$ trees yield $120\, nuts$ per $ year,$ and $(x-2)$ trees yield $180 \,nuts$ per $year$. If the average yield per $year$ per tree be $100,$ find the value of $x .$

easy

The average marks in English subject of a class of $24$ students is $56 .$ If the marks of three students were misread as $44,45$ and $61$ of the actual marks $48,59$ and $67,$ respectively, then what would be the correct average?

medium

The average age of a graph of $9$ students is $20\, years.$ When $6$ more students joined the group, the average age falls by $2\, years.$ Then the average age of new students is

Solution

Similar Questions

The average marks obtained by $180$ students in an examination is $50 .$ If the average marks of passed students is $40 .$ Then what is the number of students who failed the examination ?

Refer to the line graph and answer the giten question. Number of candidates who qualified in a given competitite examination from $6$ states during two given $years$ What is the average number of candidates who qualified in the given competitive exam from states $Q,$ $S , T$ and $U$ in $2004 ?$

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

In a coconut grove, $(x+2)$ trees yield $60$ $nuts$ per $year,$ $x$ trees yield $120\, nuts$ per $ year,$ and $(x-2)$ trees yield $180 \,nuts$ per $year$. If the average yield per $year$ per tree be $100,$ find the value of $x .$

The average marks in English subject of a class of $24$ students is $56 .$ If the marks of three students were misread as $44,45$ and $61$ of the actual marks $48,59$ and $67,$ respectively, then what would be the correct average?

Refer to the line graph and answer the giten question.

Number of candidates who qualified in a given competitite examination from $6$ states during two given $years$

What is the average number of candidates who qualified in the given competitive exam from states $Q,$ $S , T$ and $U$ in $2004 ?$

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