Estimating Sums

Front

What is estimating sums?

Back

Estimating sums is the process of finding an approximate total by rounding numbers before adding them.

Front

How do you round to the nearest ten?

Back

Look at the digit in the ones place. If it's 5 or more, round up. If it's less than 5, round down.

Front

Estimate the sum: Round to the nearest 10
437 + 37

Back

480

Front

How do you round to the nearest hundred?

Back

Look at the digit in the tens place. If it's 5 or more, round up. If it's less than 5, round down.

Front

Estimate the sum: Round to the nearest hundred
567 + 962

Back

1,600

Front

Estimate the sum: 62 + 35

Back

100

Front

Estimate the sum: 54 + 92

Back

140

Front

Estimate the sum: 5,023 + 6,243

Back

11,000

Front

What is the purpose of estimating sums?

Back

To quickly find an approximate total without calculating the exact answer.

Front

What is rounding?

Back

Rounding is adjusting a number to make it simpler while keeping its value close to what it was.