Chapter 11.2, Problem 52SR

To determine

To Check: Is Kendra correct? Explain.

Answer to Problem 52SR

Kendra is correct.

Explanation of Solution

Given:

The Brooks family can drive to the beach which is $220$ miles away, in $4$ hours if they drive $55$ miles per hour. Kendra says that they would save at least a half an hour if they were to drive $65$ miles per hour.

Given: distance= $220$ miles

We know that

  $\text{time=}\frac{\text{distance}}{\text{speed}}$

Speed = $65$ miles per hour.

Then

  $\begin{array}{l}\text{time=}\frac{\text{distance}}{\text{speed}}\\ time=\frac{220}{65}=3.4hr\end{array}$

Then

Number of hours saved

  $\begin{array}{l}=(4-3.4)hr\\ =0.60>0.5hr\end{array}$

Hence, Kendra is correct.