Home » There are m boys and 12 girls in a class. What is the probability of…

There are m boys and 12 girls in a class. What is the probability of…

There are m boys and 12 girls in a class. What is the probability of selecting at random a girl from the class?
  • A.
    (frac{m}{12})
  • B.
    (frac{12}{m})
  • C.
    (frac{12}{m+12})
  • D.
    (frac{12}{m-12})
Correct Answer: Option C
Explanation

Prob. (a girl) (=frac{Numberhspace{1mm} ofhspace{1mm} girls}{Number hspace{1mm} of hspace{1mm} boys hspace{1mm} and hspace{1mm} girlshspace{1mm} in hspace{1mm} class}\
= frac{12}{m+12})

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