Question

if the of 2,4,6,8,2,4,3,x,9 is 5.find the value of x

Answer 1

Given

• Mean of 2,4,6,8,2,4,3,x,9 is 5.

To Find

• Value of x

Concept used

• $\bf \: mean = \dfrac{sum \: of \: all \: observation}{number \: of \: observation}$

Solution

We have the mean of the given numbers but we have to find one of the number

To Find mean we use

$\bf \: mean = \dfrac{sum \: of \: all \: observation}{number \: of \: observation}$

Here we also use this formula

But we put the value which are given

• mean=5
• Sum of all observation=2+4+6+8+2+4+3+x+9
• Number of observation=Number of numbers which are given=9

Putting values

$\rm \: 5 = \dfrac{2+4+6+8+2+4+3+x+9}{9} \\ \\ \rm \implies 5 \times 9 = 38 + x \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \\ \\ \implies \rm \: 45 - 38 = x \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \\ \\ \implies \rm \boxed{ \bf \: x = 7} \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \:$