Question 162301
Marcie can walk 8 miles in the same time as Frank walks 6 miles. If Marcie walks 1 mile per hour faster than Frank, then how fast does each person walk?
:
Let s = F's walking speed
then
(s+1) = M's walking speed
:
It says the times are equal; write a time equation: Time = {{{dist/speed}}}
M's time = F's time
{{{8/((s+1))}}} = {{{6/s}}}
Cross multiply
8s = 6(s+1)
8s = 6s + 6
8s - 6s = 6
2s = 6
s = {{{6/2}}}
s = 3 mph is F's speed
and
4 mph is M's speed
:
;
Check solutions by ensuring the times are equal:
8/4 = 2hr
6/3 = 2hr