# Rounding to significant figures (Part 1)

## Lesson details

### Key learning points

1. In this lesson, we will be introduced to significant figures and understand the concept of degrees of accuracy. We will also learn how to round whole numbers to a given significant figure.

### Licence

This content is made available by Oak National Academy Limited and its partners and licensed under Oak’s terms & conditions (Collection 1), except where otherwise stated.

## Video

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## Worksheet

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## Starter quiz

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### 6 Questions

Q1.
What does this symbol mean? ≈
Equal to
Not equal to
Q2.
Find an approximation for:
18
27
27.3
Q3.
A student is thinking of an approximate value for √(67 ). What should her answer be?
2√(17) because that is the answer my calculator gives
Correct answer: 8 because √(64) is 8
8.24 because that is the exact answer to 2 d.p.
9 because 67 is closer to 70
Q4.
Find an approximation for:
10.5
15
22.5
Q5.
Find an approximation for:
25
44
55.7
Q6.
Why is the approximation to this calculation greater than the actual answer?
Carlos rounded down when he was approximating
Correct answer: Carlos rounded up for when approximating

## Exit quiz

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### 6 Questions

Q1.
What does degree of accuracy mean?
How long a measurement is
How many decimal points in a number
Correct answer: How precise a measure is, usually shown in the number of decimal places or significant digits
Measurements only rounded to a given significant figure
Q2.
How many significant figures does 0.0045 have?
1 s.f.
4 s.f.
5 s.f.
Q3.
How many significant figures does 5610 have?
2 s.f.
4 s.f.
Q4.
Rounding 405.3 to the nearest integer is the same as rounding to ________ significant figures.
1 s.f
2 s.f
4 s.f
Q5.
Round 7906 to 3 s.f.
7900