Final answer:
To calculate the discounted price of a $55.50 meal with a 20% coupon, you multiply $55.50 by 0.20 to find the discount amount ($11.10), subtract it from the original price to get $44.40. Then, calculate a 15% tip on the new price ($6.66), and add it to get the final cost of $51.06.
Step-by-step explanation:
Let's choose $55.50 as the cost of a meal for a family.
Part A: Calculating the Discounted Price
A 20%-off coupon reduces the meal's price. To calculate the discount: Convert 20% to the decimal 0.20, and multiply it by $55.50:
$55.50 × 0.20 = $11.10
Subtract the discount from the original price to find the new price:
$55.50 - $11.10 = $44.40
Part B: Calculating the Tip and Final Cost
Next, calculate a 15% tip on the discounted price. Convert 15% to 0.15, and multiply by $44.40:
$44.40 × 0.15 = $6.66
Add the tip to the discounted price:
$44.40 + $6.66 = $51.06
The final cost of the meal after applying the 20%-off coupon and adding a 15% tip is $51.06.