# Formulas and Circles

## Quiz by Andrew Watts

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17 questions
• Q1

What is the formula for the circumference of a circle?

$2\pi r$

$2\pi r^2$

$d\pi r$

$\pi r^2$

30s
• Q2

What is the formula for the circumference of a circle?

$A=2r\pi$

$C=2r+\pi$

$C=\pi d$

$C=\frac\left\{1\right\}\left\{2\right\}\pi d$

30s
• Q3

What does the prefix "Circum" mean?

To go around

A Circle

All of something

30s
• Q4

What is the formula for diameter of a circle?

$r\cdot2$

$r\div2$

$2rd$

$r^2$

30s
• Q5

How many squares fit inside a circle?

3.14 x $r^2$

3.14

$\pi r$

$d\times2$

30s
• Q6

What is the formula for the area of a circle?

$A=\frac\left\{C\right\}\left\{2\right\}\cdot r$

$A=\pi\cdot3.14r$

$C=\frac\left\{r\right\}\left\{2\right\}\cdot\pi$

$A=3.14d$

30s
• Q7

What is the formula for the area of a rectangle?

$\frac\left\{C\right\}\left\{2\right\}\times width$

$length\ \div width$

$length\ \times width$

$2\times length\ \times width$

30s
• Q8

What is the formula for the perimeter of a rectangle?

$l\cdot w$

$l+l+l+l$

$2w\times2l$

$2\ \times\left\left(l\ +w\right\right)$

30s
• Q9

What is a squared number?

A number multiplied by its self 2 times.

A number multiplied by 2.

A number that adds itself 2 times.

A number multiplied by itself.

30s
• Q10
30s
• Q11

Which number is not a perfect square?

82

121

49

64

30s
• Q12

How many diameters are in a circle's perimeter?

3.14

$d=2$

$\pi r^2$

6.28

30s
• Q13

In the image what is a chord?

ab

od

oe

cd

30s
• Q14

In the image what is a radius?

oc

cd

ab

oe

30s
• Q15

This is the diameter of a circle.

false
true
True or False
30s

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