#### Answer

The median is the average of middle two values of ordered list. Hence:
Median = (66 + 66)/2 = 66
First quartile lies at 25% of data, so $Q_{1} = 65$
Third quartile lies at 75% of data, so $Q_{3} = 70$
The IQR is the difference between $Q_{3}$ and $Q_{1}$, so:
$IQR = Q_{3} - Q_{1} = 70 – 65 = 5$
b. The mean is the sum of all values divided by number of values,so:
$Mean = 8725/130 = 67$