The record for a marathon is 4 h, 21 min, 21 s. The marathon distance is 83.16 km. Determine the average speed in m/s of a runner achieving this record.

I thought I got the right answer... but apparently it's wrong. I divided 83160, which is km in meters by 14421, which is the time in seconds. BUT ITS STILL WRONG.

HELP ME! Pleaseeee:]

4 hr = 240 min + 21 min = 261 min X 60 sec = 15660 sec + 21 sec = 15681 sec.

You divided by the wrong number. It should be 15,681 seconds.

There are 83,160 meters. This was ran in 15,681 seconds.

\frac{83160}{15681} =\frac{27720}{5227}\approx 5.303 \;\ \frac{m}{s}

That is a good pace. That translates to about 11.86 mph.