Question 278227
one runner can run 3 miles per hour faster than another.
 in the same time that the slower runner travels 3 miles, the other travels 4 miles.
 Find the speed of the slower runner.
:
Let s = rate of the slower runner
then
(s+3) = rate of the faster runner
:
Write a time equation: time = dist/speed
{{{3/s}}} = {{{4/(s+3)}}}
cross multiply
4s = 3(s+3)
4s = 3s + 9
4s - 3s = 9
s = 9 mph is the slow runner
:
:
Check solution by finding the time of each
3/9 = 1/3 hr
4/12 = 1/3 hr also