Question

The mean monthly salary of 10 members of a group is ₹ 1445, one more member whose monthly salary is ₹ 1500 joins the group. Find the mean monthly salary of 11 members of the group.

• A. 1400
• B. ₹1460
• C. ₹1480
• D. ₹1450

Answer 1

The correct option is D ₹1450

We know that,
$\Rightarrow \overline{X}=\frac{1}{n}(\sum x_i)$
$\Rightarrow n\overline{X}=\sum x_i$

Given that,
$n=10and\overline{X}=₹1445$

Now,
$\Rightarrow n\overline{X}=\sum x_i$
$\Rightarrow 10\times 1445=\sum x_i$
$\Rightarrow 14450=\sum x_i$

So, total monthly wages of 10 person = ₹ 14450
Monthly salary of one more person who joins the group is ₹ 1500

$\therefore$ Total Monthly wages of 11 people
= ₹ 14450 + ₹ 1500 = ₹ 15950

Hence, average monthly salary to 11 people
$=\frac{Totalmonthlywages}{11}$
$=\frac{15950}{11}$
$=₹1450$