I Can Add and Subtract Decimals

Watch the video on this page, and then complete the practice problems.

Use your whiteboard and marker to work out each problem.

​

Adding and Subtracting Decimals

Numbers without a decimal point

If a number does not have a decimal point, add the decimal point at the end of the number.

Multiple Choice

How do you write the number 824 as a decimal?

• 8.24

• 0.824

• 82.4

• 824.0

Multiple Choice

3.74 + .049

• 37.89

• 3.789

• 4.23

• Line Up Your Decimals! :)

Multiple Choice

91.55 + 7.6=

• 99.15

• 98.15

• 99.10

• 98.1

Fill in the Blanks

What is the difference of 2.17-0.8?

Multiple Choice

7.41 + .741

• 14.82

• 7.82

• 14.82

• 8.151

Multiple Choice

210 + .95

• 3.05

• 210.95

• 305

• 3.105

Multiple Choice

6.1477 + 2.03

• 8..1480

• 6.3507

• 8.1377

• 8.1777

Multiple Choice

420.39 + 4.2039

• 4,245,939

• 424.5929

• 8.4078

• 424.5939

Multiple Choice

Which is correct when you put the decimal points?

Multiple Choice

59,807.022 + .321

• 91,907.022

• 59,907.343

• 59.807.333

• 59,807.343

Multiple Choice

43.34 + 304.43

• 73.773

• 72.777

• 347.77

• 346.87

Multiple Choice

Which one is correct when you line up the decimal points?

Multiple Choice

8.4 - 3.03=

• 5.33

• 5.37

• 5.43

• 4.33

Multiple Choice

Solve: 55.9 - 14.948

• 40.952

• 41.293

• 40.628

• 39.081

Multiple Choice

Julie and Doug are building a tree house out of wood boards. Julie has a board that is 1.15 meters long and Doug has board that is 0.7 meter long. What is the combined length of their boards?

Two students solved the problem. Who is correct?

Multiple Choice

85.37 $$-$$ 25.679

• -111.049

• 111.049

• 59.691

• -59.691