# Aneesha travels at a rate of 50 miles per hour. Morris is traveling 3 feet per second less than Aneesha. Which is the best estimate of the speed Morris is traveling?

Jun 17, 2018

A reasonable estimate of Morris's speed would be $58$ miles/hour

#### Explanation:

The phrasing of the question implies that there should have been a list of values to choose from but no such list was provided.

$3 \left(\text{feet")/("second}\right)$
$\textcolor{w h i t e}{\text{XXX")=3("feet")/("second") xx 60("seconds")/("minute")xx60("minutes")/("hour}}$

$3 \times \left(60 \times 60\right) = 3 \times 3600$ which is a little more that $10 , 000$

So $3 \left(\text{feet")/("second}\right)$ is a little more that $10 , 000 \left(\text{feet")/("hour}\right)$

There are $5 , 280$ feet in a mile.
If we round this down to $5 , 000$ feet per mile.

then we have an estimated speed difference of
color(white)("XXX")(10,000 "feet"/"hour")/(5,000 "feet"/"mile")=2 "miles"/"hour"

So Morris is travelling at approximately $2 \text{miles"/"hour}$ less than Aneesha's given $60 \text{miles"/"hour}$
or at approximately $58 \text{miles"/"hour}$

As a point of interest, using a spreadsheet to calculate the difference in traveling at 60 miles per hour versus 58 miles per hour gave a value of $2.93 \overline{3}$ feet per second; pretty close to the requested $3$ feet per second.