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How would I solve this question? A plumbing company charges $75 per hour with a $100 inspection fee. A sales tax of 8.25% is thencalculated based on the charges (subtotal). How much would the total charge be for 3 hours of service?

How would I solve this question? A plumbing company charges $75 per hour with a $100 inspection-example-1
User Grzaks
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1 Answer

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Given

A plumbing company charges $75 per hour with a $100 inspection fee.

A sales tax of 8.25% is then calculated based on the charges (subtotal).

To find:

How much would the total charge be for 3 hours of service?

Step-by-step explanation:

It is given that,

A plumbing company charges $75 per hour with a $100 inspection fee.

And, a sales tax of 8.25% is then calculated based on the charges (subtotal).

Then,

The cost of job which takes h hours is,


c(h)=75h+100

And, the sales tax bases on the charges of h hours is,


\begin{gathered} s(c(h))=s(75h+100) \\ =0.0825(75h+100) \end{gathered}

Therefore, the total charge for h hours of service is,


\begin{gathered} t(h)=c(h)+s(c(h)) \\ =(75h+100)+0.0825(75h+100) \\ =(75h+100)(1+0.0825) \\ =(75h+100)(1.0825) \end{gathered}

Then, for h=3,


\begin{gathered} t(3)=(75*3+100)(1.0825) \\ =(225+100)(1.0825) \\ =325*1.0825 \\ =351.8125 \\ =351.8 \end{gathered}

Hence, the total charge for 3 hours of service is $351.8.

User Janusman
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