



 
Hi Zander, Suppose that the time it taker her to drive to Ceres is $t$ hours and she drives at a rate of $v$ kilometers per hour. Since rate is distance divided by time \[v = \frac{180}{t} \mbox{ or equivalently } 180= t \times {v}.\] For the return trip the time it takes is $t + 1$ hours and the speed is $v  30$ kilometers per hour. Us the fact that rate is distance divided by time for the return trip to write a second equation. Solve these equations for $v.$ Penny 



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