Very Confused About What's Supposed to Be Simple

[Guest]

Mark can run a lap in 63 seconds, if 4 laps are in a mile, what is his speed in miles per hour. Find the time it would take for Mark to finish a marathon.

I understand I have to use dimensional analysis, but i don't know where to start!

 

[Denis]

Mark can run a lap in 63 seconds, if 4 laps are in a mile, what is his speed in miles per hour. Find the time it would take for Mark to finish a marathon.
I understand I have to use dimensional analysis, but i don't know where to start!

1 mile = 4 * 63 = 252 seconds
1 hour = 60 * 60 = 3600 seconds ; just divide

How many miles in the marathon? :evil:

"dimensional analysis" :shock:
Looks like your teacher wants to sound important