Add and Subtract Decimals

Front

What is the process for adding decimals?

Back

To add decimals, align the numbers by the decimal point, add the digits starting from the rightmost column, and carry over if necessary. Place the decimal point in the sum directly below the aligned decimal points.

Front

How do you subtract decimals?

Back

To subtract decimals, align the numbers by the decimal point, subtract the digits starting from the rightmost column, and borrow if necessary. Place the decimal point in the difference directly below the aligned decimal points.

Front

What is the value of 34.80 + 17.49?

Back

The value is 52.29.

Front

How do you find the difference between two decimal areas, such as 61.44 cm² and 35.52 cm²?

Back

Subtract the smaller area from the larger area: 61.44 - 35.52 = 25.92 cm².

Front

What is the best way to estimate the sum of two decimal numbers?

Back

Round each number to the nearest whole number and then add the rounded numbers.

Front

What is the sum of 25.65, 13.23, and 6.35?

Back

The sum is 45.23.

Front

How do you combine two decimal times, such as 32.15 seconds and 31.67 seconds?

Back

Add the two times together: 32.15 + 31.67 = 63.82 seconds.

Front

What is the importance of aligning decimal points when performing addition or subtraction?

Back

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

Front

What is a bar diagram and how is it used in solving decimal problems?

Back

A bar diagram visually represents quantities, making it easier to understand relationships and perform calculations involving addition or subtraction.

Front

What is mental math and how can it be applied to decimal addition?

Back

Mental math involves performing calculations in your head without writing them down. For decimal addition, round numbers to simplify the process.