Estimating answers

In this lesson, we will learn how to estimate the answer to a calculation by rounding all the values to one significant figure before calculating.

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Quiz:

Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Q1.What is the upper bound of 21 cm rounded to the nearest centimetre?

1/5

Q2.The population of Yorkshire is 5 400 000 to two significant figures, what is the greatest possible number of people who live in Yorkshire?

2/5

Q3.What is the lower bound for 120, rounded to the nearest 5?

3/5

Q4.A rectangle has sides of 5.6 cm and 8.4 cm rounded to the nearest millimetre. What is the lower bound for the perimeter?

4/5

Q5.The side length of a square is rounded to the nearest tenth of a centimetre and used to calculate its area of 38.44 cm². What is the lower bound for the perimeter of the square?

5/5

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Unit quizzes are being retired in August 2023

Why we're removing unit quizzes from the website >
Quiz:

Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Q1.What is the upper bound of 21 cm rounded to the nearest centimetre?

1/5

Q2.The population of Yorkshire is 5 400 000 to two significant figures, what is the greatest possible number of people who live in Yorkshire?

2/5

Q3.What is the lower bound for 120, rounded to the nearest 5?

3/5

Q4.A rectangle has sides of 5.6 cm and 8.4 cm rounded to the nearest millimetre. What is the lower bound for the perimeter?

4/5

Q5.The side length of a square is rounded to the nearest tenth of a centimetre and used to calculate its area of 38.44 cm². What is the lower bound for the perimeter of the square?

5/5

Video

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Worksheet

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This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Unit quizzes are being retired in August 2023

Why we're removing unit quizzes from the website >
Quiz:

Estimating answers

Estimate answers to calculations by rounding numbers to one significant figure before calculating.

Q1.Which calculation would we do to estimate the answer to 467 ÷ 0.48?

1/5

Q2.2. Estimate the answer to 34 x 890

2/5

Q3.Estimate the answer to 273 ÷ (0.64 + 0.853)

3/5

Q4.Which of the following calculations would have as estimated answer of 1000?

4/5

Q5.5. Would the estimate for 743 x 3299 be an overestimate or an underestimate?

5/5

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Unit quizzes are being retired in August 2023

Why we're removing unit quizzes from the website >
Quiz:

Estimating answers

Estimate answers to calculations by rounding numbers to one significant figure before calculating.

Q1.Which calculation would we do to estimate the answer to 467 ÷ 0.48?

1/5

Q2.2. Estimate the answer to 34 x 890

2/5

Q3.Estimate the answer to 273 ÷ (0.64 + 0.853)

3/5

Q4.Which of the following calculations would have as estimated answer of 1000?

4/5

Q5.5. Would the estimate for 743 x 3299 be an overestimate or an underestimate?

5/5

Lesson summary: Estimating answers

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This was the final lesson in the unit Rounding and Estimating.

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