Question

1. In a study of how students use their mobile telephones, the phone usage of a random sample of 11 students was examined for a particular day. The total length of calls, in minutes, for the 11 students were 10 14 15 13 9 20 (a) Find the mean and median for these data. 14 8 12 5 11​

Answer 1

Explanation:

the mean value (or average) is simply the sum of all data values divided by the number of data points (11 in our case).

the median is the number, where half of the remaining numbers is smaller and the other half is larger.

so, we need to sort the values first :

5 8 9 10 11 12 13 14 14 15 20

so, the median is 12 minutes.

now, for the mean value :

the sum of all values above is 131.

the mean value is

131/11 = 11.909090909... minutes.

so, mean and median are almost the same. but only almost.