Out of seven given numbers, average of first four numbers is 4 and that of last four numbers is also

English

Gujarati

Hindi

4.Average

easy

Out of seven given numbers, the average of the first four numbers is $4$ and that of the last four numbers is also $4 .$ If the average of all the seven numbers is $3,$ then fourth number is?

A

$3$

B

$4$

C

$7$

D

$11$

Solution

The $4^{\text {th }}$ Number $=4 \times 4+4 \times 4-7 \times 3=32-21=11$

Therefore the $4^{\text {th }}$ Number is $11 .$

Standard 13

Quantitative Aptitude

Share

Similar Questions

A man spends on an average $Rs.\, 269.47$ for the first $7 \,months$ and $Rs.\, 281.05$ for the next $5\, months.$ Find out his monthly salary if he saved $Rs.\,308.46$ during the $year.$ (in $Rs.$)

hard

A cricketer scored some runs in his continuous $9$ innings. He scored $100$ runs in his $10^{th}$ innings and this increased his average by $8$ runs. What was the average of his runs at the end of $10^{th}$ innings?

medium

The average weight of $3$ person is $65 \,kg$. If a fourth person having a weight of $45 \,kg$ joins the group, what is the average weight of the group ? (in $kg$)

medium

The average salary of all workers in a workshop is $Rs.\, 12000 .$ The average salary of $7$ technicians is $Rs.\, 15000$ and the aterage salary of the rest in $Rs.\, 9000$. The total number of workers in the workshop is:

medium

The cost of $5 \,kg$ of apples is $Rs.\, 450 .$ The cost of $12$ dozen mangoes is $Rs.\, 4320$, and the cost of $4 \,kg$ of oranges is $Rs.\,240.$ What is the total cost of $8 \,kg$ of apples$, 8$ dozens of mangoes and $8 \,kg$ of oranges ? (in $Rs.$)

medium