Given Boston Marathon distance = 26.2 miles = 42164.81 m
And the record time to cover this distance is 1 hour 18 minutes and 27 seconds.
Let us convert that time to seconds = 1*60*60+18*60+27 = 4707 seconds
Average speed =

=

Time taken to complete 30 miles(48280.3 meters) at 8.96 m/sec is =
= 1 hour 29 minutes 48 seconds