Answer:
IQR = 10
Explanation:
1. Find the median (middle data point.)
2. Find the median of the upper quartile (70 - 80.)
3. Find the median of the lower quartile. (60 - 70.)
4. Subtract the lower quartile from upper quartile.
1. median of the data = 70
2. median of Q2 = 75
3. median of the Q3 = 65
4. 75 - 65 = 10
IQR = 10