Question

a gallon of gas costs $5.72, including tax. dong put 8 gallons of gas in his car. the tax for gas in his state is 4%. how much did dong pay in tax? round your answer to the nearest hundredth.

Explanation:

Step1: Find total cost including tax

Total cost including tax = cost per gallon × number of gallons = $5.72 × 8 = $45.76

Step2: Let the pre - tax cost be \(x\)

We know that the total cost including tax is the pre - tax cost plus 4% of the pre - tax cost. So, \(x+0.04x = 45.76\)
Combining like terms, we get \(1.04x=45.76\)
Solving for \(x\), we have \(x=\frac{45.76}{1.04}=\$44\)

Step3: Calculate the tax amount

Tax amount = total cost including tax - pre - tax cost = \(45.76 - 44=\$1.76\)
Or we can calculate it as 4% of the pre - tax cost: \(0.04\times44 = 1.76\)

Answer:

\(\$1.76\)