Unit 5

Unit 5 Lesson 4

Let's apply what we know about signed numbers to money.

Agenda

• Warm-Up: Activity 4.1

• Activity 4.2: Cafeteria Food Debt

• Activity 4.3: Bank Statement

Warm-Up

Buying Tickets

Multiple Choice

Priya is buying concert tickets for her friends with the money she earns at her part-time job. This month, she has earned $135.

Can she buy three $50 tickets for a concert?

Be prepared to explain why.

Activity 4.2

Cafeteria Food Debt

Cafeteria Food Debt

We are going to answer several questions about Kiran and his Cafeteria Debt. Read the following situation to see where we are starting with Kiran.

At the beginning of the month, Kiran had $24 in his school cafeteria account. Use a variable to represent the unknown quantity in each transaction and write an equation to represent it. Then use a number line.

Multiple Choice

In the first week he spent $16 on lunches. How much was in his account then?

He started with $24 at the beginning of the month.

Which equation best shows the scenario described above?

• -24 + 16 = -8

• 24 + 16 = 40

• 24 + -16 = 8

• -24 + -16 = -40

Open Ended

Why does it make sense to use a negative number to represent Kiran's account balance when he owes money?

Discussion

What do you notice?

What do you wonder?

DEPOSIT

to put money in

WITHDRAWAL

to take money out

Open Ended

If we put withdrawals and deposits in the same column, how can they be represented?

Multiple Choice

Andre withdraws $40 to buy a new music player.

What is his new balance?

**HINT**

To find the starting amount, look at the balance column.

• -$102.47

• -$22.47

• $102.47

• $22.47

Open Ended

If Andre deposits $100 in this account, will he still be in debt? How do you know?

Poll

How do you feel about adding positive and negative integers?