Stan took Lily to his friend’s restaurant on a date. The friend told the waiter to remove the $12 dessert from Stan’s bill. Stan tipped the waiter 20% on the reduced bill, which was a $15 tip. Fill in the blanks to write an equation that will determine the amount of the original bill, b .
The original bill, denoted by b, can be determined by the equation:
b - 12 + (0.20(b - 12)) = b
where b - 12 represents the reduced bill after removing the dessert, 0.20(b - 12) represents the tip, and (b - 12) + 0.20(b - 12) = b represents the total bill including tip.