Estimating Sums

Front

What is estimation in mathematics?

Back

Estimation is the process of finding an approximate value that is close enough to the right answer, often used when exact calculations are not necessary.

Front

How do you round a number to the nearest ten?

Back

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

Front

Estimate the sum of 71 and 85 by rounding each number to the nearest ten.

Back

70 + 80 = 150.

Front

Estimate the sum of 322 and 478 by rounding each number to the nearest hundred.

Back

300 + 500 = 800.

Front

What is the estimated sum of 123 and 456 when rounded to the nearest hundred?

Back

100 + 500 = 600.

Front

How do you estimate the sum of two numbers?

Back

To estimate the sum, round each number to a convenient value and then add those rounded values.

Front

What is the estimated sum of 62 and 35 when rounded to the nearest ten?

Back

60 + 40 = 100.

Front

Why is estimation useful in everyday life?

Back

Estimation helps in making quick calculations, budgeting, and assessing quantities without needing exact numbers.

Front

What is the estimated sum of 437 and 37 when rounded to the nearest ten?

Back

440 + 40 = 480.

Front

What is the difference between exact and estimated sums?

Back

Exact sums provide the precise total, while estimated sums give a close approximation that is easier to calculate.