Of three numbers whose average is 60, first is one-fourth of sum of others. first number is

English

Gujarati

Hindi

4.Average

medium

Of the three numbers whose average is $60,$ the first is one-fourth of the sum of the others. The first number is

A

$30$

B

$36$

C

$42$

D

$45$

Solution

Let the First $no = x$

Sum of the other numbers $=4 x$

According to the question

$\frac{x+4 x}{3}=60 \Rightarrow 5 x=180 \Rightarrow x=36$

Standard 13

Quantitative Aptitude

Share

Similar Questions

The average of $11$ numbers is $10.9$ If the average of the first six is $10.5$ and the average of last six is $11.4,$ find the middle (sixth) number.

medium

Sachin Tendulkar has a certain average for $11$ innings. In the $12^{th}$ innings he scores $120$ runs and thereby increases his average by $5$ runs. His new average is

medium

The average age of a husband and wife, who were married $7 \,years$ ago, was $25\, years$ at the time of their marriage, Now, the average age of the family, including husband, wife and a child, born during the interval, is $22\, years.$ What is the present age of the child in $year$ ?

easy

Fifteen movie theatres average $600$ customers per theatre per day. If $six$ of the theaters close down but the total theater attendance stays the same, then the average daily attendance per theatre among the remaining theaters is

hard

The average age of a family of $6$ members is $22\, years.$ If the age of the youngest member be $7\, years,$ then what was the average age of the family at the birth of the youngest member?

medium