SOLUTION: The time "t" that it takes Hannah to bike to school varies inversely as her average speed, "s". If she can bike to school in 25 minutes her average speed is 6 mi/h. What would her

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Question 940655: The time "t" that it takes Hannah to bike to school varies inversely as her average speed, "s". If she can bike to school in 25 minutes her average speed is 6 mi/h. What would her average speed need to be to get to school in 20 min.?
I got 7.5 mph. Is this correct?
Thank you!
Found 2 solutions by ankor@dixie-net.com, josgarithmetic:
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
Answer by josgarithmetic(39613) About Me  (Show Source):
You can put this solution on YOUR website!
t=k%2Fs, t for time, s for speed, k for proportionality constant. Here, k must mean distance. Notice the units used. t in minutes, and speed seems used as miles per hour.

st=k
k=6%2A25


Find s if t is 20 minutes?
t=k%2Fs
st=k
s=k%2Ft
s=6%2A25%2F20
s=%282%2A3%2A5%2A5%29%2F%282%2A2%2A5%29
s=15%2F2
Speed is 7.5 miles per hour.