Rounding Numbers to Estimate the Sum Flashcard

Front

What is rounding in mathematics?

Back

Rounding is the process of adjusting the digits of a number to make it simpler and easier to work with, while keeping its value close to what it was.

Front

What is the purpose of rounding numbers?

Back

The purpose of rounding numbers is to simplify calculations, make estimates easier, and provide a more manageable number for practical use.

Front

What does it mean to round to the nearest ten?

Back

Rounding to the nearest ten means adjusting a number to the closest multiple of ten.

Front

How do you round a number that is exactly halfway between two multiples?

Back

If a number is exactly halfway between two multiples, you typically round up to the higher multiple.

Front

What is the rule for rounding numbers that are less than five?

Back

If a digit is less than five, you leave the preceding digit unchanged.

Front

What is the rule for rounding numbers that are five or greater?

Back

If a digit is five or greater, you add one to the preceding digit.

Front

What is the estimated sum of 45 and 36 when rounded to the nearest ten?

Back

The estimated sum is 80 (rounded 45 to 50 and 36 to 40, then 50 + 40 = 90).

Front

What is the estimated sum of 790 and 112 when rounded to the nearest hundred?

Back

The estimated sum is 900 (rounded 790 to 800 and 112 to 100, then 800 + 100 = 900).

Front

What is the sum of 7 and 1?

Back

The sum of 7 and 1 is 8.

Front

What is the sum of 8 and 1?

Back

The sum of 8 and 1 is 9.