Estimating by Rounding in Subtraction

The video tutorial explains how to estimate the result of subtracting large numbers by rounding them to the nearest ten. It uses a practical example of counting candies to illustrate the concept. The process involves rounding the numbers involved to make mental calculations easier, demonstrating the utility of estimation in everyday situations.

What is the initial number of candies in the container?

• 59

• 220

• 60

• 282

Tags

CCSS.2.OA.A.1

How many candies did the friend eat?

• 60

• 59

• 50

• 282

What does the wavy equal sign (~=) represent in mathematics?

• Exactly equal

• Approximately equal

• Greater than

• Less than

Tags

CCSS.3.NBT.A.1

CCSS.4.NBT.A.3

To which number is 282 rounded when estimating?

• 290

• 300

• 270

• 280

Tags

CCSS.3.NBT.A.1

CCSS.4.NBT.A.3

What is the nearest ten to which 59 is rounded?

• 55

• 50

• 70

• 60

Tags

CCSS.2.NBT.B.7

CCSS.3.NBT.A.2

What is the result of subtracting 60 from 280?

• 260

• 240

• 200

• 220

Tags

CCSS.1.NBT.C.5

How many tens are left after subtracting 6 tens from 28 tens?

• 22

• 20

• 24

• 18

Tags

CCSS.5.NBT.B.7

What is the purpose of rounding numbers in estimation?

• To get an exact answer

• To simplify calculations

• To confuse the problem

• To make calculations harder

Why is estimation a useful skill?

• It is only for small numbers

• It simplifies complex problems

• It helps with exact calculations

• It is not useful

What is the final estimated number of candies left?

• 282

• 59

• 220

• 60