Question

If the mean of x,x+2,x+4,x+6andx+8 is 13 find the value of x​

Answer 1

Given:-

If the mean of x,x+2,x+4,x+6 and x+8

The mean is 13

To Find:-

The Value of x

Formulae used:-

Mean = $\rm{\dfrac{sum/:of/:all/: observation}{Number/:of/: observation}}$

Now,

→ Sum of all observation = $\rm{ x + x +2 + x + 4 + x + 6 + x + 8}$

→ Sum of all observation = 5x + 20

→ Number of Observation = 5

Therefore,

→ Mean = $\rm{\dfrac{5x + 20}{5}}$

→ 13 = $\rm{\dfrac{5x + 20}{5}}$

→ 13 × 5 = 5x + 20

→ 65 = 5x + 20

→ 65 - 20 = 5x

→ 45 = 5x

→ x = 45/5

→ x = 9

Hence, The Value of x is 9

Answer 2

Data Given :

The mean of = x, x + 2, x + 4, x + 6, x + 8

Mean = 13

We should find :

Value of x

Our problem will be,

Mean = Sum of all observations / No. of. observations

We have 5 observations here.

Mean = [ x + ( x + 2 ) , ( x + 4 ) , ( x + 6 ) + ( x + 8 ) ] / 5

= 13 = 5x + 20 / 5

= 13 × 5 = 5x + 20

= 65 = 5x + 20

= 65 - 20 = 5x

= 45 = 5x

= x = 45 / 5

= x = 9

Value of x = 9