Mental Math Strategy

Mental Math

Strategy 4

Read and Understand

Multiple Choice

999 rounded to the nearest thousand is?

• 990

• 900

• 1000

• 0

Multiple Choice

5673 + 1000 =

• 6673

• 3673

• 5573

• 5663

Multiple Choice

6673 - 1 =

• 6573

• 3673

• 5663

• 6672

Fill in the Blanks

5673 + 999 =

Fill in the Blanks

2845 + 999 =

Fill in the Blanks

7331 + 999 =

Did you notice...

The THOUSANDS went up by one...



 while the UNITS went down by one.

Fill in the Blanks

3258 + 999 =

Did you see?

1234 becomes 2233.

2491 becomes 3490

The thousand digit goes UP.
The unit/one digit goes DOWN

Fill in the Blanks

1472 + 999

Are you ready to do it a bit faster now?

Try do it as fast as you can!

Fill in the Blanks

8221 + 999 =

Fill in the Blanks

5347 + 999 =

Fill in the Blanks

6210 + 999 =

Fill in the Blanks

1111 + 999

Fill in the Blanks

3692 + 999 =