You did not include the table.
I will use this table that I found for a problem with the same statement, and for sure this will teach how to proceed, and it might even be the same data that of your table:
Division Record Holder Year Time (h)
Men's open Robert Cheruiyot 2006 2.121
Women's open Margaret Okayo 2002 2.345
Men's wheelchair Ernst VanDyk 2004 1.305
Women's
wheelchair Jean Driscoll 1994 1.523
Miles per our
Just divide the distance (26.2 miles) by the time in hours
Robert 26.2 miles / 2.121 hours = 23.372 miles / hour
Margaret 26.2 miles / 2.345 hours = 11.173 miles / hour
Ernst 26.2 miles / 1.305 hours = 20.077 miles / hour
Jean 26.2 miles / 1.523 hours = 11.203 miles / hour