Find the median of the data: 1,5,3,7,9,2,4,7,1

Given data: 1,5,3,7,9,2,4,7,1

Now, arrange the data in ascending order, we get:

1, 1, 2, 3, 4, 5, 7, 7, 9

Here, the number of observations is 9, which is odd.

Thus, median = 5th term

Median = 4.