Foundation

Foundation

# Find the radius and diameter when given the area

## Lesson details

### Key learning points

1. In this lesson, we will learn how to find the radius or diameter of a circle when given the area. This lesson will involve rearranging the formula for the area of a circle.

### 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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### 4 Questions

Q1.
Find the area of the circle in terms of π.
A
B
D
Q2.
Find the area of the circle to three significant figures.
A
C
D
Q3.
Find the area of the circle to 3 significant figures.
A
B
D
Q4.
Find the area in terms of π.
A
C

## Exit quiz

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### 4 Questions

Q1.
What is missing from this rearranged formula?
a) They forgot to square the fraction
b) The fraction should be A over π
c) hey haven’t square rooted the fraction
Correct answer: d) Both b) and c)
Q2.
What will this formula find?
The area of a circle
The circumference of a circle
Correct answer: The diameter of a circle
Q3.
Find the radius of this circle to three significant figures.
A
B
C