Decimals

Lesson

Now that you've had some practice adding decimals, you can try adding decimals of larger quantities. Follow the same steps as before. You can use estimation to see if your answer makes sense!

Watch the steps in the video below. At the end, see how to estimate quickly to check your answer.

Front-End Estimation

Round by removing the numbers after the decimal point. Add your two numbers. Is the sum close to the sum of the decimals? If not, try your decimal sum again!

Find $33.42+37.33$33.42+37.33 giving your answer as a decimal.

Find $24.56+36.44$24.56+36.44 giving your answer as a decimal.

Find $72.36+1.64$72.36+1.64 giving your answer as a decimal.

Add and subtract decimal numbers to hundredths, including money amounts, using concrete materials, estimation, and algorithms (e.g., use 10 x 10 grids to add 2.45 and 3.25)