Question

93, 94, 95, 89, 85, 82, 87, 85, 84, 80, 78, 78, 84, 87, 90.

-Calculate the mean and median closing price.

Answer 1

Mean = 86.067

Median = 85

Explanation:

The given data set is

{ 93, 94, 95, 89, 85, 82, 87, 85, 84, 80, 78, 78, 84, 87, 90 }

Number of observations = 15

Formula for mean:

`Mean=(\sum x)/(n)`

where, n is number of observations.

Using the above formula, we get

`Mean=(93+94+95+89+85+82+87+85+84+80+78+78+84+87+90)/(15)`

`Mean=(1291)/(15)`

`Mean\approx 86.067`

Therefore the mean of the given data set is 86.067.

Arrange the given data set in ascending order.

{ 78, 78, 80, 82, 84, 84, 85, 85, 87, 87, 89, 90, 93, 94, 95 }

Number of observation is 15 which is an odd term. So

`Median=((n+1)/(2))\text{th term}`

`Median=((15+1)/(2))\text{th term}`

`Median=8\text{th term}`

`Median=85`

Therefore the median of the data set is 85.