Rounding and Estimating Decimals

Front

What is rounding in mathematics?

Back

Rounding is the process of adjusting the digits of a number to make it simpler while keeping its value close to what it was. It often involves increasing or decreasing the last digit based on the value of the next digit.

Front

What does it mean to estimate a sum?

Back

Estimating a sum involves finding a rough calculation of the total by rounding the numbers involved before adding them together.

Front

How do you round a decimal to the nearest whole number?

Back

To round a decimal to the nearest whole number, look at the digit in the tenths place. If it is 5 or greater, round up; if it is less than 5, round down.

Front

What is the approximate symbol in mathematics?

Back

The approximate symbol is represented as '≈' and is used to indicate that two values are close to each other but not exactly equal.

Front

How do you estimate the difference between two decimal numbers?

Back

To estimate the difference, round each number to a convenient value (often a whole number) and then subtract the rounded values.

Front

What is the process of rounding 4.8 to the nearest whole number?

Back

4.8 rounds to 5 because the tenths place (8) is greater than 5.

Front

When estimating, why is it important to choose convenient numbers?

Back

Choosing convenient numbers makes mental calculations easier and quicker, allowing for faster estimations.

Front

What is the result of estimating the sum of 16.9 and 8.3?

Back

When estimating, 16.9 rounds to 17 and 8.3 rounds to 8, so the estimated sum is 17 + 8 = 25.

Front

What is the difference between exact and approximate values?

Back

Exact values are precise and unrounded, while approximate values are rounded or estimated to simplify calculations.

Front

How do you determine if a number will round up or down?

Back

Look at the digit immediately to the right of the place value you are rounding to. If it is 5 or higher, round up; if it is 4 or lower, round down.