Adding and subtracting money means combining or taking away amounts of dollars and cents. You work with money amounts the same way you work with decimals because each amount has a dollar part and a cent part.
If you have $5.25 and you find $2.00 more, you now have $7.25.
Money amounts are written as decimals. The decimal point separates dollars from cents.
When you add or subtract money, always line up the decimal points so the digits are in the correct place values: dollars under dollars and cents under cents.
If the cents column adds to 100 or more, regroup by turning 100 cents into 1 dollar.
To add money, line up the decimals, add the cents, then add the dollars. Regroup when needed.
You buy a notebook for $4.75 and a folder for $2.50. How much do you spend?
Check your answer by estimating. For example, $4.75 is close to $5 and $2.50 is close to $3. So the total should be close to $8.
To subtract money, line up the decimals, subtract the cents, then subtract the dollars. If the top cents digit is smaller, borrow from the dollars.
You have $20.00, and you spend $8.65. How much is left?
Borrowing in money subtraction is the same as borrowing with decimals. One whole dollar becomes 100 cents.
Money questions often come from real-life situations, such as shopping, saving, or making change. Use addition when amounts are combined and subtraction when money is spent or taken away.
You have $15.00. You buy a snack for $3.45 and a drink for $1.75. How much money do you have left?
Step 1: Add the cost of the items.
Step 2: Subtract from the amount you started with.
Ask yourself: “Am I putting amounts together or finding what is left?” This helps you choose the correct operation.