Question 1111895
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Her speed is {{{180/3}}} = 60 miles per hour.


At this speed she needs  {{{540/60}}} = 9 hours to drive 540 miles.


Alternatively, you can write and solve a proportion


{{{180/3}}} = {{{540/x}}} 


and find the unknown time x.


Notice that the both sides of the proportion express the same speed !
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