Adding and Subtracting Decimals

Front

What is a decimal?

Back

A decimal is a fraction expressed in a special form. It uses a decimal point to separate the whole number part from the fractional part.

Front

How do you add decimals?

Back

To add decimals, align the numbers by the decimal point and add as you would whole numbers, placing the decimal point in the sum directly below the other decimal points.

Front

How do you subtract decimals?

Back

To subtract decimals, align the numbers by the decimal point and subtract as you would whole numbers, placing the decimal point in the difference directly below the other decimal points.

Front

What is the sum of 2.98 and 5.3?

Back

8.28

Front

What is the difference between 864.2 and 363.3?

Back

500.9

Front

If a file is 50.30 GB and the total size is 93 GB, how do you find the size of the second file?

Back

Subtract the size of the first file from the total size: 93 - 50.30 = 42.70 GB.

Front

Annie buys shoes for $47.82 and a top for $13.36. How do you calculate her change from $100?

Back

Add the costs: 47.82 + 13.36 = 61.18. Then subtract from $100: 100 - 61.18 = 38.82, approximately $39.

Front

What is the total rainfall if City A received 3.74 inches and City B received 9.8 inches?

Back

Add the rainfall amounts: 3.74 + 9.8 = 13.54 inches.

Front

What is the importance of aligning decimal points when adding or subtracting?

Back

Aligning decimal points ensures that each digit is in the correct place value, which is crucial for accurate calculations.

Front

What is a common mistake when adding decimals?

Back

A common mistake is not aligning the decimal points, which can lead to incorrect sums.