Adding & subtracting decimals word problem
About this video
Leo has $4,522.08, deposits $875.50 and withdraws $300. Sal adds the deposit by lining up the decimals to get $5,397.58, then writes $300 as $300.00 and subtracts to find $5,097.58 left.
You'll be able to
- decide whether a deposit or withdrawal means adding or subtracting.
- add and subtract money amounts by lining up the decimal points.
- write a whole dollar amount with zero cents, like $300.00.
Key words
- deposit
- Putting money into a bank account, so you add it.
- withdraw
- Taking money out of a bank account, so you subtract it.
- hundredths (cents)
- A penny is one hundredth of a dollar, so cents are in the hundredths place.
Transcript
Leo has $4,522.08 in his bank account. He deposits another $875.50 and then withdraws $300 in cash. How much is left in his account? So he's starting with $4,522.08. Let's write that down. $4,522.08. And then he deposits, or he adds, another $875.50. So he's going to add $875.50.
When you deposit into an account, you're putting something into the account, or you're adding to the account. So after he adds that $875.50, what does he have? We go back to the penny spot, or we could view that as the hundredths. A penny is one hundredth of a dollar.
Let me switch colors. We have 8 plus 0 is 8. 0 plus 5 is 5. We have the decimal right there. 2 plus 5 is 7. 2 plus 7 is 9. 5 plus 8 is 13. Put the 3 down here and regroup the 1, or carry the 1. 1 plus 4 is 5. So after the $875.50 deposit, he has $5,397.58. Then he withdraws $300 in cash, or he takes out $300, so we'll have to subtract that.
So then he withdraws $300 and I just added some trailing zeroes after the decimal. $300 is the same thing as $300.00 and zero cents. And then we subtract. 8 minus 0 is 8. 5 minus 0 is 5. We have our decimal right there. 7 minus 0 is 7. 9 minus 0 is 9. 3 minus 3 is 0, and then 5 minus nothing here is 5.
So he's the left with, in his account, $5,097.58.
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