# One lap around a dirt track is 1/3 mile. It takes Bryce 1/9 hour to ride one lap. What is Bryce’s unite rate, in miles, around the track?

Jun 26, 2018

2 miles per hour

#### Explanation:

$\textcolor{b l u e}{\text{Method}}$

what we are looking for is miles in 1 hour mph
->("miles")/("hour") -> "miles" -:"hours"

So the unit of measurement of miles per hour is telling us that we divide the time into the distance.

Distance $\div$ time $\textcolor{w h i t e}{\text{d")->color(white)("d") 1/3" mile" -: 1/9" hours"color(white)("ddd") =color(white)("ddd") (1/3-:1/9) color(white)("d")("miles")/("hour}}$

We have divided the numbers $\left(\frac{1}{3} \div \frac{1}{9}\right)$ and we have divided the unites of measurement $\left(\text{miles")/("hour}\right)$
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$\textcolor{b l u e}{\text{The calculation}}$

$\frac{1}{3} \div \frac{1}{9} \textcolor{w h i t e}{\text{ddd") ->color(white)("ddd") 1/cancel(3)^1xxcancel(9)^2/1color(white)("d")=color(white)("d")2color(white)("d")("miles")/("hour}}$