Question

Find the difference between the arithmetic means of all even and odd numbers between 50 and 60.

Answer 1

The even numbers between 50 and 60 are 52, 54, 56 and 58.
The odd numbers between 50 and 60 are 51, 53, 55, 57 and 59.

The arithmetic mean of even numbers between 50 and 60 is
$=\frac{52+54+56+58}{4}$
$=\frac{220}{4}$
$=55$

The arithmetic mean of odd numbers between 50 and 60 is
$=\frac{51+53+55+57+59}{5}$
$=\frac{275}{5}$
$=55$

$\therefore$ Required difference = 55 - 55 = 0