Estimate Sums Using Rounding

Front

What does it mean to round a number?

Back

Rounding a number means adjusting it to the nearest ten, hundred, or other place value to make it easier to work with.

Front

How do you round a number to the nearest ten?

Back

Look at the digit in the ones place. If it is 5 or more, round up. If it is 4 or less, round down.

Front

Round 569 to the nearest ten.

Back

570

Front

Round 342 to the nearest ten.

Back

340

Front

What is the sum of 570 and 340 after rounding?

Back

910

Front

What is the halfway number between 180 and 190?

Back

185

Front

Round 314 to the nearest ten.

Back

310

Front

Round 421 to the nearest ten.

Back

420

Front

What is the estimated sum of 310 and 420?

Back

730

Front

Round 149 to the nearest ten.

Back

150