Question 62543
Given values are 7, 19, 19, N, 15

Their mean is given to be 13.

Which means the sum of the given values divided by 5 = 13

==> (7 + 19 + 19 + N + 15)/5 = 13
==>  (60 + N)/5 = 13
==> 60 + N = 65  [multiplying by 5 on both the sides]
==> 60 + N - 60 = 65 - 60
==> N = 5

So the unknown value = 5.

Mean is nothing but the average of the given values.

To find the median we first arrange these values in one order.
That is ascending or descending.
 ==> 5, 7, 15, 19, 19

The middle value is called the median 
Here the median = 15.

Mode is the most frequantly occured value.

Here 19 is repeated and so mode = 19.

Good Luck!!!