SOLUTION: How do I set up this word problem equation? Ruth and Jerry Mackin go for an outing in Memorial Park in Houston, Texas. Ruth jogs while Jerry rollerblades. Jerry rollerblades 2

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Question 416345: How do I set up this word problem equation?
Ruth and Jerry Mackin go for an outing in Memorial Park in Houston, Texas.
Ruth jogs while Jerry rollerblades. Jerry rollerblades 2.9 miles per hour faster than Ruth jogs. When Jerry has rollerbladed 5.7 miles, Ruth has jogged 3.4 miles. Find Ruth's jogging speed.
Thank you
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Ruth jogs while Jerry rollerblades. Jerry rollerblades 2.9 miles per hour faster than Ruth jogs.
When Jerry has rollerbladed 5.7 miles, Ruth has jogged 3.4 miles.
Find Ruth's jogging speed.
:
Let s = R's jogging speed
then
(s+2.9) = J's rolling speed
:
Write a time equation; time = dist/speed
:
rolling time = jogging time
5.7%2F%28s%2B2.9%29 = 3.4%2Fs
Cross multiply
5.7s = 3.4(s+2.9)
5.7s = 3.4s + 9.86
5.7s - 3.4s = 9.86
2.3s = 9.86
s = 9.86%2F2.3
s = 4.287 mph is R's jogging time
:
:
Check solution by finding the times (J's speed 2.9+4.287 = 7.187)
5.7/7.187 = .793 hrs
3.4/4.287 = .793 hrs; confirms our solution of s = 4.287