JEE Math Practice Question
A bag contains 30 white balls and 10 red balls. 16 balls are drawn one by one randomly from the bag with replacement. If X be the number of white balls drawn, then $$\left( {{{mean\,\,of\,X} \over {s\tan dard\,\,deviation\,\,of\,X}}} \right)$$ is equal to :
- A.4
- B.$$3\sqrt 2 $$
- C.$${{4\sqrt 3 } \over 3}$$
- D.$$4\sqrt 3 $$
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