Severity: Warning

Message: count(): Parameter must be an array or an object that implements Countable

Filename: controllers/formulas.php

Line Number: 37

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n! = n ( n – 1 ) … 2 ( 1 )

C ( n, r ) = n! / r! ( n – r )!

=> Combination of 12 choose 3 is given as = 12! / 3! 9!

= (12 x 11 x 10) / (3 x 2 x 1) = 4 x 5 x 11 = 220

=> Answer : there are 220 different groups of 3 students that may be chosen from a group of 12 students.

=> Combination of 52 choose 4 is given as = 52! / 4! 48!

= (52 x 51 x 50 x 49) / (4 x 3 x 2 x 1) = 13 x 17 x 25 x 49 = 270725

=> Answer : There are 270725 4 card hands possible.