Answer
median = 25.3
$Q_{1} = 20.9125
$Q_{3} = 29.6875
Interquartile range = 8.775
Work Step by Step
For a normal distribution, the mean and median are assumed to be approximately the same.
To find the quartiles, we need to determine the z-value where 25% of the population is above (or below) the mean. This value is .675 (and -.675), respectively.
$(x - 25.3)/6.5 = .675$
$(x - 25.3) = 4.3875$
$ Q_{3} = 30 (rounded up from 29.6875)$
$(x - 25.3)/6.5 = -.675$
$(x - 25.3) = -4.3875$
$ Q_{1} = 21 (rounded up from 20.9125)$
$29.6875-20.9125= 8.775$
