Adding and Subtracting Decimals (1st Period)

Front

What is a decimal?

Back

A decimal is a fraction whose denominator is a power of ten, represented with a decimal point. For example, 0.5 is a decimal representation of 5/10.

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 importance of lining up decimal points when adding or subtracting?

Back

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

Front

If Linda had $20 and spent $16.78, how do you find her change?

Back

Subtract the total spent from the amount she had: $20.00 - $16.78 = $3.22.

Front

What is the result of 56.6 mL - 3.2 mL - 6 mL?

Back

First, subtract 3.2 mL from 56.6 mL to get 53.4 mL. Then subtract 6 mL to find the remaining solution: 53.4 mL - 6 mL = 47.4 mL.

Front

How do you calculate the total cost including tax?

Back

To calculate the total cost including tax, multiply the original price by the tax rate and add that amount to the original price.

Front

If Albert paid $73.49 with a $100 bill, how do you find his change?

Back

Subtract the amount paid from the amount given: $100.00 - $73.49 = $26.51.

Front

What is the difference in height between two trees measuring 54.2 cm and 47.6 cm?

Back

Subtract the shorter height from the taller height: 54.2 cm - 47.6 cm = 6.6 cm.

Front

What is the first step in solving a decimal addition problem?

Back

The first step is to align the numbers by their decimal points.