Hi, Lesliamine! :)
1 hour= 60 minutes
60+18
=78 mins and 27 secs.
or 78.45 minutes.
To find the average speed per mile, divide the time by distance.
78.45/26.2
=2.99427481
or 2 minutes and 59.6564886 secs.
It takes 2.99427481 minutes to complete a mile.
To find how long it would take to finish 30 miles, multiply the time per mile by 30 miles.
2.99427481*30
=89.8282443 minutes
or 89 minutes and 49.694658 secs
or an hour and 29 minutes and 49.694658 secs.
Hope this helps.
-Benjamin