Answer:
Each of the workouts plans lasts 45 minutes.
Explanation:
Let the duration for Plan A workout = x
Let the duration for Plan B workout = y
Friday
• Plan A --> 3 clients
,• Plan B --> 5 clients
,• Kala trained her Friday clients for a total of 6 hours
[tex]3x+5y=6[/tex]Saturday
• Plan A --> 9 clients
,• Plan B --> 7 clients
,• Kala trained her Saturday clients for a total of 12 hours
[tex]9x+7y=12[/tex]The system of equations is solved simultaneously.
[tex]\begin{gathered} 3x+5y=6\cdots(1) \\ 9x+7y=12\cdots(2) \end{gathered}[/tex]Multiply equation (1) by 3 in order to eliminate x.
[tex]\begin{gathered} 9x+15y=18\cdots(1a) \\ 9x+7y=12\cdots(2) \end{gathered}[/tex]Subtract.
[tex]\begin{gathered} 8y=6 \\ y=\frac{6}{8}=0.75\text{ hours} \\ 0.75\times60=45\text{ minutes} \end{gathered}[/tex]Substitute y=0.75 into equation (2) to solve for x.
[tex]\begin{gathered} 9x+7y=12 \\ 9x+7(0.75)=12 \\ 9x+5.25=12 \\ 9x=12-5.25=6.75 \\ x=\frac{6.75}{9} \\ x=0.75 \end{gathered}[/tex]x=y=0.75 hours = 45 minutes,
Each of the workouts plans lasts 45 minutes.