Chapter 4.5, Problem 27PPE

(a)

To determine

To Calculate: Amount of money left after buying a meal.

Answer to Problem 27PPE

Cost	Amount remaining
15	$55-(15+15·0.15)=37.75$
21	$55-(21+21·0.15)=30.85$
24	$55-(24+24·0.15)=27.40$
30	$55-(30+30·0.15)=20.5$

Explanation of Solution

Given information: You had 55 when you entered the restaurant. Also the meal costs 15, 21, 24 and 30

Calculation: Make a table using the given meal costs. Tip is 15%. Divide by 100 to remove the percentage (0.15).To find the amount paid for the meal, multiply meal cost with tip and add it with meal cost. The calculation and the table is given below

Cost	Amount remaining
15	$55-(15+15·0.15)=37.75$
21	$55-(21+21·0.15)=30.85$
24	$55-(24+24·0.15)=27.40$
30	$55-(30+30·0.15)=20.5$

(b)

To determine

To identify: the function rule for the amount of money left after buying a meal.

Answer to Problem 27PPE

The function rule is $m=55-1.15c$

Explanation of Solution

Given information: You had 55 when you entered the restaurant and a tip 15%.

Calculation: Let ‘c’ be the meal cost and ‘m´ be the amount of money left.

To get the function rule, multiply the tip with the meal cost and add it with the meal cost. Finally subtract the cost with tip from the amount you have.

  $\begin{array}{l}money\_left=55-(\cos t+\cos t·0.15)\\ m=55-(c+c·0.15)\\ m=55-1.15c\end{array}$

The function rule is $m=55-1.15c$

(c )

To determine

To graph: Graph the function rule using the table

Answer to Problem 27PPE

  

Explanation of Solution

Given information: Table from part (a)

Cost	Amount remaining
15	37.75
21	30.85
24	27.40
30	20.50

Graph: Use the cost and amount remaining from the table as coordinates (x,y) and graph the table