Waiting for a Friend: Solving a Time Difference Problem

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SUMMARY

The problem involves two individuals driving 50 km at different speeds: one at 91.4 km/hr and the other at 88.3 km/hr. The calculated travel times are 0.547 hours for the first driver and 0.566 hours for the second driver, leading to a wait time of 0.019 hours. The discrepancy arises from potential expectations regarding significant figures or time units in the computer-generated exercise, which may not align with the straightforward calculation performed.

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  • Understanding of basic kinematics and speed-distance-time relationships
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  • Knowledge of unit conversions, particularly between hours and minutes
  • Experience with problem-solving in algebraic contexts
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  • Review the concept of speed-distance-time calculations in physics
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Homework Statement



You and a friend each drive 50 km. You travel at a uniform speed of 91.4 km/hr and your friend travels at a constant speed of 88.3 km/hr. How long will you wait for your friend?


Homework Equations





The Attempt at a Solution



So I thought I could just set up a ratio and cross-multiply to get the hrs. traveled by each person. I got .547hrs. for "me" and .566hrs. for "my friend". Then subtract, the difference being the answer. However, I am doing this on a computer-generated exercise and it is telling me that .019hrs. is incorrect. Why isn't this right?
 
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It looks like you did this correctly, I get the same answer. It could be they expect a different number of significant figures in the answer, or they expect different time units for some reason.
 

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