Find the number of ways of selecting 8 subjects from 12 subjects for an examination
-
A.
490 -
B.
495 -
C.
496 -
D.
498
Correct Answer: Option B
Explanation
Combination is the number (n) of ways of selecting a number of (m) of objects from n
(^{12}C_{8}frac{12!}{8!(12-8)!}\=frac{12!}{8!4!}\frac{(12times 11times 10times 9times 8times 7times 6times 5times 4times 3times 2times 1)}{8times 7times 6times 5times 4times 3times 2times 1}\Afterhspace{1mm} cancelling hspace{1mm}out hspace{1mm}wehspace{1mm} have\11times 5times 9 = 495 )