Gujarati
Hindi
4.Average
medium

The $average$ of $30$ numbers is $12 .$ The $average$ of the first $20$ of them is $11$ and that of the next $9$ is $10 .$ The last number is

A

$60$

B

$45$

C

$40$

D

$50$

Solution

Sum of all $30$ Number $=30 \times 12=360$

The last Number $=360-(20 \times 11+9 \times 10)$

$=360-(220+90)=50$

Standard 13
Quantitative Aptitude

Similar Questions

Start a Free Trial Now

Confusing about what to choose? Our team will schedule a demo shortly.