Adding and Subtracting Decimals

Front

What is the process for adding decimals?

Back

To add decimals, align the numbers by the decimal point, add zeros if necessary to make the numbers the same length, and then add as you would with 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, add zeros if necessary to make the numbers the same length, and then subtract as you would with whole numbers, placing the decimal point in the difference directly below the other decimal points.

Front

What is the value of 7.05 - 4.6?

Back

The value is 2.45.

Front

What is 21 + 4.09?

Back

The sum is 25.09.

Front

What is the result of 9.43 − 3.34?

Back

The result is 6.09.

Front

Calculate 2.98 + 5.3.

Back

The sum is 8.28.

Front

If the Bell family drove for 10.9 hours, 8.6 hours, and 12.4 hours, how do you find the total time?

Back

To find the total time, add the three durations together: 10.9 + 8.6 + 12.4 = 31.9 hours.

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 should you do if the numbers have different lengths when adding or subtracting decimals?

Back

You should add zeros to the end of the shorter number to make both numbers the same length before performing the operation.

Front

What is a common mistake when adding or subtracting decimals?

Back

A common mistake is misaligning the decimal points, which can lead to incorrect sums or differences.