how to figure state taxes on the dollar

Question

i bought 4 new tires for my car at 89.95 per tire. I was also charged for the following, tire mounting 3.95, 1.65 for tire valves,and 4.10 per tire for balancing, which came to 398.20 total. I can i figure the state taxes on the dollar

Answer 1

4 tires at 89.95=359.80$

4 balans at 4.10=16.40$

mount=3.95

valves=1.65

sum=381.80

kost=398.20, so tax=398.2-381.80=16.40$

tax rate=16.40/181.80=0.04295

=4.3%