Question

You and two of your friends go to eat pizza

together. There are two deals:

1. 10% off of 1 pizza )

2. 30% off of 3 pizzas

Do you want to each pay separately and get

10% off of your bill, or do you want to split the

bill 3 ways and get 30% off of 3 pizzas?

Write a response that convinces your teacher

Answer 1

The second deal offers a lower cost for the three friends.

Explanation:

Let consider that each pizza has a price
`c_(o)`. Now, we proceed to check the total cost for each case, the better choice is whose total cost after discounts is the lowest.

Case 1 - 10 % off of 1 pizza (Split costs and buy 3 pizzas separately)

`C = 0.9\cdot C_(o) + 0.9\cdot C_(o) + 0.9\cdot C_(o)`

`C = 2.7\cdot C_(o)`

The cost for each person is:

`c = (C)/(3)`

`c = 0.9\cdot C_(o)`

Case 2 - 30 % off of 3 pizzas (Split costs and buy 3 pizzas in a row)

`C = 0.7\cdot (3\cdot C_(o))`

`C_(o) = 2.1\cdot C_(o)`

The cost for each person is:

`c = (C)/(3)`

`c = 0.7\cdot C_(o)`

The second deal offers a lower cost for the three friends.