Final answer:
To calculate the tip, multiply the total bill by the tip percentage. In this case, the total bill is $25.50 and the tip is 10%, so the tip amount is $2.55. To find the total bill including the tip, add the tip amount to the original bill. The total bill with the tip is $28.05.
Step-by-step explanation:
To calculate the tip, multiply the total bill by the tip percentage. In this case, the total bill is $25.50 and the tip is 10%, so the tip amount is $25.50 x 0.10 = $2.55.
To find the total bill including the tip, add the tip amount to the original bill. The total bill with the tip is $25.50 + $2.55 = $28.05.