The following data provides marks of 20 students. You are required to calculate the median marks.

25, 72, 28, 65, 29, 60, 30, 54, 32, 53, 33, 52, 35, 51, 42, 48, 45, 47, 46, 33.

45.5

The correct answer is Option 3: 45.5

Step 1: Arrange the data in Ascending or descending order.

Arranging the data in an ascending order, we get 25, 28, 29, 30, 32, 33, 33, 35, 42, 45, 46, 47, 48, 51, 52, 53, 54, 60, 65, 72.

Step 2: We can see that there are two observations in the middle, 45 and 46. The median can be obtained by taking the mean of the two observations:

Median = (45+46)/ 2 = 45.5 marks