Question 102961
Suppose that Wendy rides her bicycle 30 miles in the same time that it takes Kim to ride her bicycle 20 miles. IF Wendy rides 5 miles per hour faster than Kim, find the rate of each.
:
Let s = K's speed
then
(s+5) = W's speed
:
Since they tell us the the two times are the same, we can make a simple time
equation from this fact: Time = Distance/Speed
:
K's time = W's time
{{{20/s}}} = {{{30/((s+5))}}}
:
Cross multiply
30s = 20(s+5)
:
30s = 20s + 100
:
30s - 20s = 100
:
10s = 100
:
s = 10 mph is K's speed and 15 mph is W's speed
:
:
Check solution by find the time of each:
20/10 = 30/15
 2 = 2