Question

Students taking a make-up test receive the following grades: 96, 80, 71, 68, 81, 75, 85, 95, 72, and 66. Which grade has a percentile rank of 30?The test score with a percentile rank of 30 is

Answer 1

It is given that the grades are:

$96,80,71,68,81,75,85,95,72,66$

Arrange the data in ascending order to get:

$66,68,71,72,75,80,81,85,95,96$

Use the formula to get the data point.

$D=\frac{np}{100}$

Here n is total number of data points, p is the percentile needed so it is 30 in this case and n=10 so it follows:

$D=\frac{10\times30}{100}=3$

So the third data point will be the 30th percentile of the data.

Hence the data point is 71.