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1 vote
1 vote
It takes Max 5.5 minutes to do 60 pullups which includes a break in between. It takes him 8

User Zkunov
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1 Answer

18 votes
18 votes

Using the given information, we have the points (5.5, 60) and (8, 150). Let's find the ratio-


r=(y_2-y_1)/(x_2-x_1)

Where


\begin{gathered} x_1=5.5 \\ x_2=8 \\ y_1=60 \\ y_2=150 \end{gathered}
\begin{gathered} r=(150-60)/(8-5.5)=(90)/(2.5) \\ r=36 \end{gathered}

This ratio represents the slope of the linear equation.

Then, we use the point-slope formula to find the equation that models this situation


\begin{gathered} y-y_1=m(x-x_1) \\ y-60=36(x-5.5) \\ y=36x-198+60 \\ y=36x-138 \end{gathered}

The correct equation is the third option.

Now, we can find the number of pulls after 30 minutes using the equation


y=36\cdot30-138=942

The number of pull-ups after 30 minutes is 942.

User Thiago Arreguy
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3.2k points