Question

What is the circumference of a pizza whose diameter is 30 cm?
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Answer 1

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What is the circumference of a pizza whose diameter is 30 cm?

${ \boxed{ \huge \sf \red{Answer}}}$

94.25 cm

The circumference of the pizza whose diameter is 30 cm is 94.25cm.

Answer 2

Digram:-

$\setlength{\unitlength}{1cm}\begin{picture}(0,0)\thicklines\qbezier(2.3,0)(2.121,2.121)(0,2.3)\qbezier(-2.3,0)(-2.121,2.121)(0,2.3)\qbezier(-2.3,0)(-2.121,-2.121)(0,-2.3)\qbezier(2.3,0)(2.121,-2.121)(-0,-2.3)\put(0,0){\line(1,0){2.3}}\put(0.5,0.3){\bf\large 15\ cm}\end{picture}$

Given:-

• diameter of pizza = 30 cm

To find:-

• circumference of pizza

Solution:-

First of all let's convert diameter into radius.

we know:

$\sf{}Diameter =2 \times radius$

$\leadsto \sf{}30=2 \times radius$

$\leadsto \sf{}2 \times radius = 30$

$\leadsto \sf{}radius = \dfrac{30}{2}$

$\leadsto \sf{}radius = \dfrac{15 \times 2}{2}$

$\leadsto \sf{}radius = \dfrac{15 \times \cancel2}{ \cancel2}$

$\leadsto \sf{}radius = \dfrac{15 \times 1}{ 1}$

$\leadsto \sf{}radius = \textsf{ \textbf{15 cm}}$

Finally Let's find circumference of pizza

We know:-

$\bigstar \boxed{ \rm{}circumference \: of \: circle = 2\pi r}$

by using this formula we can find value of circumference of pizza

$\dashrightarrow \: \sf{}circumference \: of \: circle = 2\pi r$

$\dashrightarrow \: \sf{}circumference \: of \: circle = 2 \times \dfrac{22}{7} \times 15$

$\dashrightarrow \: \sf{}circumference \: of \: circle =\dfrac{22 \times 2 \times 15}{7}$

$\dashrightarrow \: \sf{}circumference \: of \: circle =\dfrac{44\times 15}{7}$

$\dashrightarrow \: \sf{}circumference \: of \: circle =\dfrac{660}{7}$

$\dashrightarrow \: \underline{\boxed{ \sf{}circumference \: of \: circle =94.29 \: cm}}$

$\therefore \underline{ \sf{}circumference \: of \: circle = \textsf{ \textbf{94.29 cm}}} \sf(approx)$