Brendan bought an iced tea that cost $4.06 plus 7% sales tax. If Brendan left an 18% tip on the $4.06, how much in total did he pay?

Step-by-step explanation:

18% tip in $=18/100 * $4.06

$0.7308

7% sales tax in $= 7/100 * $4.06

$0.2842

Total amount he paid= $0.7308+$0.2842+$4.06

$5.07500

  $5.07

Step-by-step explanation:

The amount of tax was ...

  7% × $4.06 ≈ $0.28

The amount of tip was ...

  18% × $4.06 ≈ $0.73

The total bill, with tax and tip, was ...

  $4.06 +$0.28 +$0.73 = $5.07

Brendan paid $5.07 in total.

Additional comment

The tax and tip are figured on the same base amount, so their percentages could be added. When you do that, you compute the total to be ...

  $4.06 × (1 +7% +18%) = $4.06×1.25 = $5.075

Ordinarily, this would be rounded up to $5.08. However, the 7% tax and the 18% tip are both rounded down to the nearest cent, so the end result is $5.07, not $5.08.