Exercise 67 Page 31

First, let's convert minutes to hours. Since $1$ hour equals $60$ minutes, we can convert the time to hours by dividing the number of minutes by $60.$

Minutes	$\frac{\text{Minutes}}{60}$	Hours
$30$	$\frac{30}{60}$	$\frac{1}{2}$
$20$	$\frac{20}{60}$	$\frac{1}{3}$

To express how much Braden works out in just $1$ week, we will need to add together the time he spends running with the time he spends lifting weights. We can form expressions for how much Braden works out by multiplying the time he spends on each activity by the number of days he does it. If he runs $6$ times a week for $\frac{1}{2}$ hour, we get the following expression. If Braden lifts weights $3$ times a week for $\frac{1}{3}$ hour, we can complete the algebraic expression for how much Braden works out in $1$ week. Since we want the expression for the number of hours Braden works out in $4$ weeks, we have to multiply our expression by $4.$ Let's evaluate the expression. In $4$ weeks he works out for $16$ hours.