Estimating Sums and Differences in Mathematics

The video tutorial explains how to use estimation to simplify calculations of sums and differences. It provides two main tips: identifying keywords that suggest estimation is needed and rounding numbers before performing operations. The tutorial includes several examples, such as calculating the number of recyclables, chicken patties, and money spent while shopping, to illustrate the application of these tips. It also highlights when exact calculations are necessary, emphasizing the importance of understanding the context of a problem.

What is the first tip for using estimation in math problems?

• Always round to the nearest ten.

• Use a calculator for exact answers.

• Look for keywords like 'about' or 'estimate'.

• Solve the problem first and then round the answer.

What should you do after identifying keywords in an estimation problem?

• Round all the numbers first.

• Ignore the keywords.

• Perform the operation first.

• Use a calculator.

If you have 234 pop cans and 178 glass bottles, approximately how many recyclables are there when rounded to the nearest hundred?

• 300

• 400

• 500

• 600

When rounding 234 to the nearest ten, what is the result?

• 200

• 230

• 240

• 250

Tags

CCSS.3.NBT.A.1

CCSS.4.NBT.A.3

If 211 chicken patties were made and 173 were eaten, approximately how many are left when rounded to the nearest ten?

• 40

• 50

• 30

• 60

Why does rounding 211 and 173 to the nearest hundred not make sense in the chicken patties problem?

• It results in a negative number.

• It results in zero.

• It results in a very large number.

• It results in an exact number.

What should you do if a problem does not contain keywords like 'about' or 'estimate'?

• Guess the answer.

• Skip the problem.

• Perform the exact calculation.

• Round the numbers anyway.

If you start with a $50 bill and spend $27.14, approximately how much money should you get back when rounded to the nearest ten?

• $40

• $10

• $20

• $30

Why is it easier to round $27.14 to $30 instead of $20?

• Because $20 is too far from $27.14.

• Because $20 is not a round number.

• Because $30 is closer to $27.14.

• Because $30 is a round number.

Tags

CCSS.5.NBT.A.4

What is the final step after rounding the numbers in an estimation problem?

• Check the keywords again.

• Perform the operation with the rounded numbers.

• Write down the original numbers.

• Round the numbers again.