Applying signed number addition to find a final balance
About this video
A theater starts the month with an $80 debt and then earns $230. The video shows how to write the debt as a negative balance, -80, and add 230 to get a final balance of $150.
You'll be able to
- represent a debt as a negative balance.
- add a positive amount to a negative balance to find a final balance.
Key words
- debt
- Money you owe, which we can show as a negative balance.
- balance
- How much money an account has after adding what comes in and taking away what goes out.
Transcript
- [Instructor] We're told a neighborhood theater starts the month with an $80 debt, then the theater earns $230 from ticket sales. What is the theater's balance after the ticket sales? Pause this video, have a go at that. All right, so if we think about it's balance.
An 80... Let me make sure you can see what I'm writing. If we think about its balance, an $80 debt, that means they owe $80. So that would be a negative balance if you thought about how much they have. So I would view this as, they started with negative $80 and then they earned $230 from ticket sales.
So plus $230. And so, what is this going to be equal to? This is going to be the same thing as 230 minus 80, 230 minus 80. If it was 240 minus 80, it would be 160. So this is just going to be $150. And we are done.
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