Question

a letter is chosen at random from the letter of the word RROBABILITY. find the probabiloty tjat is not a vowel.

Answer 1

there are total 26 letters and out of which 5 are vowel 
so,
26-5=21
so 21 are the left letters
now,
probability= sum of observation upon total no of observation
so,
21/ 26 => 0.807


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