Finding percentiles
The cumulative distribution function allows us to find the proportion of values that are x or lower.
The inverse can also be done from the cumulative distribution function. Given any proportion, p, we can find a value x such the proportion of values that are x or lower is approximately p. This is called the p'th quantile of the data set.
When p is given as a percentage, the same value is called the p'th percentile.
Annual rainfall in Dodoma