The median and interquartile range for the cleverites are : 25 and 20 respectively. 
The slowest club on average is the Braineys
From https://brainly.com/question/14724605?referrer=searchResults : 
The median value for the cleverites : 
The Median is the time at the midpoint of the frequency curve : 
Median frequency = Cummulative frequency / 2 
Median frequency = 80 /2 = 40
Tracing to the intersection point on the curve and reading the x - value at the point of intersection ; 
- Median for the Cleverites is 25
The interquartile range = (upper quartile - lower quartile) 
Upper quartile = 3/4(Cummulative frequency) = 3/4(80) = 60 
Upper quartile = 35 minutes 
Lower quartile = 1/4(80) = 20
Lower quartile = 15 minutes 
Interquartile range = (35 - 15) = 20 minutes 
To obtain the slowest club on average, we could use the median :
Median for Cleverites = 25
Median for Braineys :
1/2(80) = 40
Time on the x axis corresponding to y = 40 is 32
Comparing the median values : 
32 > 25 
Braineys > Cleverites ;
The slowest on average at competing is Braineys as they have a higher completion time. 
Learn more : https://brainly.com/question/14724605