Noah and Ben are running in the Walker Street Fun Run Noah r

Noah and Ben are running in the Walker Street Fun Run. Noah runs at 7
mph, Ben at 5 mph. If they start at the same time, how long (in minutes)
will it be before they are 1/3 miles apart?

Solution

D=RT
D+1/3=7T OR D=7T-1/3 FOR NOAH
D=5T FOR BEN.
SET THE D EQUATION EQUAL 7 SOLVE FOR T.
7T-1/3=5T
7T-5T=1/3
2T=1/3
T=(1/3)/2
T=1/3*1/2=1/6 HOURS OR 10 MIN.
PROOF:
7/6-1/3=5/6
7/6-2/6=5/6
5/6=5/6