Using money is an important life skill.
In this lesson, we're going to explore how to add and subtract money.
Let's say you're buying some items at a supermarket.
To know the total cost of the items you're buying, you need to add money.
For example, let's say you're looking to buy these two items.
How much should you pay for them? 🤔
👉 First, write the amounts in column, or vertical form.
Tip: You only have to write the dollar sign with the first number.
When you write the numbers, make sure that the decimal points are lined up correctly.
A decimal point is the dot that separates the dollars on its left and the cents on its right.
We start by adding the rightmost digits, then we go left.
Don't forget to bring down your decimal point and the dollar sign when you write your answer.
We see that the total is $2.95! ✅
That's 2 dollars and 95 cents. 😃
You're buying two jigsaw puzzles. Each puzzle costs $2.85.
How much should you pay for these? 🤔
You just have to double the amount. Double means to add the amount to itself.
👉 Now, we arrange the numbers in column form first.
Be sure to line up the decimal points.
👉 Then, we add the numbers.
We add the digits in the Hundredths column first.
Tip: The Hundredths column is different from the Hundreds column (no -ths)!
We see that we need to regroup.
We place 0 in the Hundredths place, and carry 1 over to the Tenths column.
We then add the digits in the Tenths column.
8 + 8 + 1 = 17
Remember to add the 1 that we carried over.
We write 7 in the Tenths place, and carry 1 over to the Dollars column.
Finally, we add the digits in the Dollars column.
2 + 2 + 1 = 5
We write 5 in the Dollar column.
😃 Don't forget to write the decimal point between 5 and 7.
✅ The total amount you need to pay is $5.70!
Another skill that you need to learn is subtracting money.
Imagine you're at a toy shop.
You see a toy with a sign that says "$2.50 Discount".
A discount means a certain amount is subtracted from the original price.
If the original price is $6.50, how can you find the final price? 🤔
You subtract!
Tip: Subtracting money is just like subtracting 3-digit numbers.
👉 First, write the numbers in column form.
Write the bigger number at the top, and the smaller number at the bottom. 😃
Make sure to line up the decimal points.
👉 Then, subtract the numbers, starting from the Hundredths place (the rightmost place)
The new price of the toy is $4.00! ✅
You also subtract money when making change.
Let's say you buy a gift for your friend.
It costs $3.35. You give the shopkeeper a $5 bill.
How much change should you get? 🤔
To know the answer, you need to subtract $3.35 from $5.
First, write the numbers in column form.
Tip: When a money amount doesn't have a decimal point, you can always add a decimal and 2 zeros after it.
That's because $5 is the same as $5.00.
Tip: make sure that the decimal points are lined up.
Now, we subtract the numbers.
Start from the Hundredths column first.
Since we can't subtract 5 from 0, we have to borrow from the next place.
😌 But wait! The next place is also 0, so we have to borrow from the place after it.
So we borrow from 5 in the Dollar place.
Now, we can subtract.
Your change should be $1.65! ✅
Tip: Review how to subtract across zeros if that's difficult for you.
Great job learning how to add and subtract money! 🎉
Now, complete the practice to help you understand more.