Tawnya bought a new sweater for $26.21, and the sales tax was 8.25%. how much sales tax did tawnya pay on the sweater?

$26.21 x 0.0825 = $2.16 is the sales tax paid if not included in the $26.21 (Total paid would be $26.21 + 2.16 = $28.37)

If $26.21 includes the sales tax:
x + 0.0825x = $26.21
1.0825x = $26.21 
x = $26.21        x = $24.21   To check: $24.21 x 1.0825 = $26.21
      1.0825                           Amount of Sales tax paid: $26.21 - $24.21 = $2.00