Step 1 Arrange the data in order from lowest to highest.
9 12 15 16 18 19 20 22 24 25

Step 2 Compute

c = \frac{n · p}{100}

where n = total number of values

p = percentile

Thus,

c = \frac{10 · 65}{100} = 6.5

Since c is not a whole number, round it up to the next whole number; in this case, it is c = 7.
Start at the lowest value and count over to the 7th value, which is 20. Hence, the value of 20 corresponds to the 65th percentile.