If I buy a stereo in my state that has a 6% sales tax and paid $360.40, including tax, what would be the price of the stereo before tax? Show equation to solve. Thanks

If I buy a stereo in my state that has a 6% sales tax and payed $360.40, including tax, what would be the price of the stereo before tax? Show equation to solve. Thanks
If Tax is 6% than $100 item would become after tax $106 so
(100/106)x360.40 would be the cost of item before tax which comes to
$340.00
Verification
$340 + $20.4 (6% of $340) = $360.40

If you need an equation:

let Price before tax = P

Price after tax = P + 6% of P = P + .06 P = 1.06 P

Hence:

1.06 P = 360.40

Solve this for P.