SOLUTION: Sylvia walked to Cathy's house at 2km/h, and then rode a bicycle back to her own house at 10km/h. The entire trip took 3 hours. How long a time did Sylvia walk?

Algebra ->  Customizable Word Problem Solvers  -> Travel -> SOLUTION: Sylvia walked to Cathy's house at 2km/h, and then rode a bicycle back to her own house at 10km/h. The entire trip took 3 hours. How long a time did Sylvia walk?      Log On

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Question 372553: Sylvia walked to Cathy's house at 2km/h, and then rode a bicycle back to her own house at 10km/h. The entire trip took 3 hours. How long a time did Sylvia walk?
Answer by ayalyaniv(6) About Me  (Show Source):
You can put this solution on YOUR website!
Since this is a distance problem, you would use the rt=d equation.
2(t)=d
10(3-t)=d
You are not given the distance between Sylvia's and Cathy's houses, but since it is a two-way trip, you know that both equations cover the same distance.
So you can write 2(t)=10(3-t)
Multiply out 2t=30-10t
Transposing you get 12t=30.
Dividing by 12 you get t=2.5
Sylvia walked for 2.5 hours (and rode for half an hour)