<PRE><B>Question 333722</B>
length of 1 round = 500+500+ pi*40   ( 2 semicircles on either end)
=1000+40*pi
=1125.66  feet is the length of 1 lap.
13 laps will be 
13 * 1125.66
=14633.62 feet
..
5280 feet = 1 mile
14633.62 feet = 146322.62/5280 
= 2.77 miles
..
40 minutes 35 seconds is the time taken for 13 laps.
=2400+35
= 2435 seconds
..
2435/3600 = 0.676 hours
speed = distance / time
=2.77 miles/0.676
= 6.9 mph
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