Estimate Sums & Differences

Front

What is estimation in math?

Back

Estimation is a way to find a number that is close to the exact amount, often used to make calculations easier.

Front

How do you estimate a sum?

Back

To estimate a sum, round each number to the nearest ten or hundred, then add the rounded numbers.

Front

How do you estimate a difference?

Back

To estimate a difference, round each number to the nearest ten or hundred, then subtract the smaller rounded number from the larger one.

Front

Estimate the sum: 46 + 37

Back

80 (round 46 to 50 and 37 to 40, then add 50 + 40 = 90).

Front

Estimate the difference: 85 - 29

Back

60 (round 85 to 90 and 29 to 30, then subtract 90 - 30 = 60).

Front

What is the nearest ten to 758?

Back

760.

Front

What is the nearest hundred to 793?

Back

800.

Front

If Ethan ran 826 miles and Jana ran 475 miles, how do you estimate how many more miles Ethan ran?

Back

Round 826 to 830 and 475 to 480, then subtract: 830 - 480 = 350.

Front

If Keaton scored 427 points and 189 points, how do you estimate his total score?

Back

Round 427 to 430 and 189 to 190, then add: 430 + 190 = 620.

Front

What is rounding?

Back

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