Question

The numbers 6, 8, 11, 12, 2x - 8, 2x + 10, 35, 41, 42, 50 are written in ascending order. If their median is 25, then what is the mean of the numbers?

• A. 24.8
• B. 24.6
• C. 25.5
• D. 25.2

Answer 1

Answer:

C. 25.5

Solution:

Calculation:

⇒ Numbers in ascending order : 6, 8, 11, 12, 2x - 8, 2x + 10, 35, 41, 42, 50

The number of terms is 10 i.e. even number.

Thus, 

Median of 10 numbers is the mean of 5^th and 6^th numbers.

$\Rightarrow \frac{(2x - 8) + (2x + 10)}{2} = 25$

$\Rightarrow 4x + 2 = 50$

$\Rightarrow x = \frac{48}{4} = 12$

Thus, sum of the numbers are = 6 + 8 + 11 + 12 + 16 + 34 + 35 + 41 + 42 + 50 = 255

∴ Mean = $\frac{255}{10}=25.5$