Question

If the median of the data a,2a,4a(a>0) is 18 then 5a =

Answer 1

Step-by-step explanation:

Given data is: a,2a,4a which are in ascending order.

n = 3 (an odd number) (n= number of data)

$\therefore \: median \: = ( \frac{n + 1}{2})^{th} \: term \\ \:\:\:\:\:\:\:\: \:\:\:\:\:\:\:\:\:\:\:\:\:\:=( \frac{3 + 1}{2})^{th} \: term \\ \:\:\:\:\:\:\:\: \:\:\:\:\:\:\:\:\:\:\:\:\:\:=( \frac{4}{2})^{th} \: term \\ \therefore \: median \: =( 2)^{nd} \: term \\\therefore 18 = 2a \: (( 2)^{nd} \: term \: is \: 2a) \\ \therefore \: a = \frac{18}{2} \\ \therefore \: \huge \boxed{ a =9} \\ \implies \: 5a = 5 \times 9 \\ \implies \: \huge \boxed{5a =45}$