When running a half marathon (13.1 miles), it took Collin 7 minutes to run from mile marker 1 to mile marker 2, and 21 minutes to run from mile marker 2 to mile marker 4.

Question

When running a half marathon (13.1 miles), it took Collin 7 minutes to run from mile marker 1 to mile marker 2, and 21 minutes to run from mile marker 2 to mile marker 4.

How long did it take Collin to run from mile marker 1 to mile marker 4?

What was Collin's average speed as he ran from mile marker 1 to mile marker 4?

75 minutes after starting the race, Collin passed mile marker 9. To complete the race in 112 minutes, what must Collin's average speed be as he travels from mile marker 9 to the finish line?

Answer 1

1) 7 + 21 = 28 min

2) (3 mi / 28 min) * (60 min / 1 hr) ~= 6.429 mph

3) [(13.1 mi - 9 mi)/(112 min - 75 min)] * (60 min / 1 hr) ~= 6.649 mph