# Area of a circle Calculator

## Calculates the area and circumference of a circle given the radius or diameter.

 radius r diameter R 6digit10digit14digit18digit22digit26digit30digit34digit38digit42digit46digit50digit area S circumference L
 $\normal Circle\\\vspace{5}(1)\ diameter:\hspace{45} R=2r\hspace{30}r:\ radius\\(2)\ area:\hspace{80} S=\pi r^2=\pi({\large\frac{R}{2}})^2\\(3)\ circumference:\ L=2\pi r=\pi R\\$
Area of a circle
 [1-10] /10 Disp-Num5103050100200
[1]  2018/11/17 11:26   Male / 20 years old level / Elementary school/ Junior high-school student / Very /
Purpose of use
To expose me more understanding
Comment/Request
nice
[2]  2018/07/23 03:43   Male / 60 years old level or over / An engineer / Very /
Purpose of use
CEU''s re-newing my certification
Comment/Request
It''s great because I don''t have to do the laborious math long hand in a note book! Where was this when I was in college? Oh, that''s right the internet, apps and calculators weren''t invented then, just the old trusty slide rule.
[3]  2017/06/15 17:28   - / 20 years old level / An engineer / Useful /
Purpose of use
To be able to ease my work of calculation
[4]  2014/03/29 09:13   Male / 60 years old level or over / An engineer / Very /
Purpose of use
verify manual calculations involved in modifing a automotive combustion engine using different varribles for optimum horsepower to torque at given RPM
[5]  2013/02/18 14:53   Male / 60 years old level or over / Self-employed people / Very /
Purpose of use
Determine area of different diameter pizzas to calculate best buy for price!
Comment/Request
Thank you !
[6]  2012/11/30 17:24   Male / Under 20 years old / High-school/ University/ Grad student / Very /
Purpose of use
assignments especially in physics
Comment/Request
great page,, very useful..
[7]  2012/11/16 13:39   Male / 20 years old level / A teacher / A researcher / Very /
Purpose of use
for exam
Comment/Request
for college level only
[8]  2011/09/29 11:22   Male / 40 years old level / Self-employed people / Very /
Purpose of use
Comment/Request
AMAZING
[9]  2009/11/04 21:08   Male / 20 level / An office worker / Very /
Purpose of use
Comment/Request
good
[10]  2009/09/10 16:59   Male / More than 60 / A teacher / Very /
Comment/Request
Very useful.

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