# Combination Calculator

## Calculates the number of combinations of n things taken r at a time.

 number of things n n≧r≧0 number to be taken r 6digit10digit14digit18digit22digit26digit30digit34digit38digit42digit46digit50digit combinations nCr
 $\normal Combinations\\\vspace{5}(1)\ {}_nC_r=\left$$n\\r\\ \right$$={\large\frac{n!}{r!(n-r)!}}\\(2)\ {}_nC_r={\large\frac{{}_nP_r}{r!}}\\$
Combination
 [1-10] /15 Disp-Num5103050100200
[1]  2018/09/22 21:48   Female / 30 years old level / An office worker / A public employee / Very /
Purpose of use
I wanted to determine the feasibility of using top categories in my trivia league to make a fun personality type thing. With 18 categories, it is not feasible.
[2]  2018/03/20 23:16   Female / Under 20 years old / High-school/ University/ Grad student / Useful /
Purpose of use
Homework
[3]  2018/02/05 02:50   Female / 50 years old level / A retired people / A little /
Purpose of use
for exercise the mind
[4]  2017/09/30 16:11   Female / 60 years old level or over / Self-employed people / Very /
Purpose of use
Space needed for an artistic design using fixed number of colors
Comment/Request
Great app!
[5]  2017/07/15 03:55   Female / 30 years old level / A homemaker / Useful /
Purpose of use
To find out how many combinations of meals I can make with all of the things I know how to cook. Seriously.
Comment/Request
nice app! Good refresher course!
[6]  2017/06/07 08:27   Male / Under 20 years old / High-school/ University/ Grad student / Useful /
Purpose of use
Designing gameplay mechanics
[7]  2017/04/27 23:52   Male / 40 years old level / An office worker / A public employee / Very /
Purpose of use
Determining Level of Effort on software development
Comment/Request
My IT guy said there was 400 combinations that had to be vetted out and I called BS. Validated with your tool... Pretty funny actually... Thanks!
[8]  2017/03/30 08:02   Male / Under 20 years old / Elementary school/ Junior high-school student / Very /
Purpose of use
HOMEWORK
Comment/Request
i LIKE IT YOU GUYS SHOULD MAKE PREDICTION GAMES
[9]  2017/02/16 13:16   Male / 30 years old level / Self-employed people / Very /
Purpose of use
research
[10]  2017/02/12 01:58   Male / 30 years old level / A teacher / A researcher / Very /
Purpose of use
To complement a research methodology.
Comment/Request
Write out the possible outcome for 90 combination 5?

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