### All AP Statistics Resources

## Example Questions

### Example Question #1 : How To Find The Quartiles For A Set Of Data

Obtain a normal distribution table or calculator for this problem.

Approximate the -percentile on the standard normal distribution.

**Possible Answers:**

**Correct answer:**

The -percentile is the value such that percent of values are less than it.

Using a normal table or calculator (such as R, using the command qnorm(0.9)), we get that the approximate -percentile is about .

### Example Question #1 : How To Find The Quartiles For A Set Of Data

Find the first and third quartile for the set of data

**Possible Answers:**

**Correct answer:**

In order to find the first and third quartiles, we haave to find the 25th and 75th percentiles, respectively.

To find the percentile, we find the product of and the number of items in the set.

We then round that number up if it is not a whole number, and the term in the set is the percentile.

For this problem, to find the and percentile, we first find that there are 14 items in the set. We find their respective products to be

and

As such, the and percentiles are the fourth and eleventh terms in the set, or