The sales tax rate for the state of Washington was 8.3%.

What is the state sales tax on a $4,300 car in Washington?
What is the final cost of the car, including tax?

4,300 * 0.083 = $356.90 sales tax

Add the sales tax to 4,300.

To calculate the state sales tax on a $4,300 car in Washington, you need to multiply the price of the car by the sales tax rate. Here's how you can do it:

1. First, convert the sales tax rate from a percentage to a decimal. You can do this by dividing the sales tax rate by 100. In this case, the sales tax rate is 8.3%, so you would divide 8.3 by 100:
8.3 ÷ 100 = 0.083

2. Next, multiply the price of the car by the sales tax rate in decimal form. In this case, you would multiply $4,300 by 0.083:
$4,300 × 0.083 = $356.90

So, the state sales tax on a $4,300 car in Washington is $356.90.

To calculate the final cost of the car, including tax, you need to add the sales tax amount to the original price of the car. Here's how to do it:

1. Add the sales tax amount of $356.90 to the original price of the car. In this case, you would add $356.90 to $4,300:
$4,300 + $356.90 = $4,656.90

So, the final cost of the car, including tax, is $4,656.90.