help in Math for school please

Question

The sales tax in Jefff's state is 5.5%. Jeff bought a new car and paid $650 in sales tax. What was the cost of the car?

Answer 1

This Jefff character, it seems, paid 5.5% in sales tax. We'll assume he paid the cost of the car in full. Call this price P. Then Jeff 5.5% of P, or (0.055)P, in sales tax. But we know he paid $650 in sales tax, and so, we can conclude (0.055)P=650. Now just solve for P, as in, P=650/(0.055). Use a calculator.

If your calculator is broken, we have (0.055)P=650, or 5(0.011)P=5(130), or (0.011)P=130, or (0.001)(11)P=130, or (11)P=(1,000)(130), or (11)P=(130,000), or P=(130,000)/11.