Question

Kensy drove to the airport to pick up her friend. A rainstorm forced her to drive at an average speed of 70 mph, reaching the airport in 3.5 hours hours. She drove back home at an average speed of 80 mph. How long, to the nearest tenth of an hour, did the trip home take her?

Answer 1

In this scenario, we have to use an inverse rule of three:

`\begin{gathered} 70mph\rightarrow3.5h \\ 80\text{mph}\rightarrow x\text{ hours} \\ \Rightarrow x=\frac{(70mph)(3.5h)}{80\text{mph}}=3.0625\text{ hours} \end{gathered}`

Therefore, the trip back took approximately 3.1 hours