Estimating Sums and Differences of Whole Numbers

This video tutorial covers estimating sums and differences of mixed numbers using benchmark fractions. It begins with an introduction to the concept, followed by a detailed explanation of how to round mixed numbers. The video includes practice exercises for rounding and concludes with methods to estimate sums and differences using rounded numbers.

What is the main goal of this video?

• To learn how to add and subtract mixed numbers exactly.

• To understand how to use benchmark fractions to estimate sums and differences of mixed numbers.

• To memorize the values of different fractions.

• To learn how to convert mixed numbers to improper fractions.

When rounding a mixed number, what should you do if the fraction part is greater than or equal to 1/2?

• Convert the fraction to a decimal.

• Keep the whole number the same.

• Round up to the next whole number.

• Round down to the nearest whole number.

If you have the mixed number 6 and 1/3, how would you round it to the nearest whole number?

• Round to the nearest half.

• Convert to an improper fraction first.

• Round down to 6.

• Round up to 7.

When rounding mixed numbers, what should you do if the fraction part is less than 1/2?

• Round up to the next whole number.

• Round to the nearest half.

• Drop the fraction and use the whole number.

• Convert the fraction to a decimal.

What is the rounded whole number for 8 and 5/6?

• 8

• 9

• 7

• 10

How would you round 7 and 40/81 to the nearest whole number?

• Round up to 8.

• Round down to 7.

• Round to the nearest half.

• Convert to a decimal first.

What is the estimated sum of 4 and 1/8 plus 7 and 2/3 when rounded to the nearest whole numbers?

• 12

• 11

• 13

• 10

If you round 2 and 1/4 and 5 and 1/2 to the nearest whole numbers, what is their sum?

• 7

• 8

• 9

• 10

What is the rounded whole number for 10 and 3/4?

• 9

• 10

• 11

• 12

What is the estimated difference of 11 and 3/5 minus 4 and 1/12 when rounded to the nearest whole numbers?

• 9

• 6

• 7

• 8