Question

The mean of 5 variables is 20. If four of them are 15, 25, 10 and 12; the fifth variable is ______.

विकल्प

• 38

• 60

• 48

• 28

Answer 1

The mean of 5 variables is 20. If four of them are 15, 25, 10 and 12; the fifth variable is 38.

Explanation:

Let fifth variable be x.

By formula,

\[\text{Mean} = \frac{\text{Sum of observations}}{\text{No. of observations}}\]

\[\therefore 20 = \frac{15 + 25 + 10 + 12 + x}{5}\]

⇒ 20 × 5 = x + 62

⇒ 100 = x + 62

⇒ x = 100 − 62 = 38