Problem 429

Fiona kept the following records of her phone bills for 12 months:

55, 50, 64, 54, 71, 57, 55, 48, 66, 71, 59, 70

Find the mean and median of Fiona’s monthly phone bills.

Solution:-

First arrange the values in ascending order which is given bellow

48, 50, 54, 55, 55, 57, 59, 64, 66, 70, 71, 71

Mean=sum of terms /number of terms

Sum of terms=48+50+54+55+55+57+59+64+66+70+71+17=720

Number of terms=12

So mean= $\frac{720}{12}$ = 60

When the number of values of even then medain =avarge of = $\frac{n}{2}$ th term and ( $\frac{n}{2}$ )+1 th term

Where n=number of terms

So here medain=[ $\frac{12}{2}$ + ( $\frac{12}{2}$ )+1]/2= $\frac{(6 th term+7 th term)}{2}$

6 th term is 57

7 th term is 59

So median= $\frac{(57+59) }{2}$ = 58