Answer:
$20.55
Step-by-step explanation:
(price last week) - 27% × (price last week) = $15 . . . . what the problem says
(price last week) × (1 - 0.27) = $15 . . . . factor out price
(price last week) = $15/0.73 . . . . . . . . . divide by the coefficient of price
(price last week) ≈ $20.55
