Question 1177223
t, time
r, "speed" average
k, proportionality constant



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amount of time it takes a swimmer to swim a race is inversely proportional to the average speed of the swimmer. 
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{{{t=k(1/r)}}}


{{{t=k/r}}}


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swimmer finishes a race in 200 seconds with an average speed of 3 feet per second.
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{{{t*r=k}}}


{{{k=200*3}}}


{{{k=600}}}


The model becomes  {{{highlight(t=600/r)}}}.
You could do the questions using this formula.