A prime number is randomly picked from list of prime numbers less than 70 , what is probability that

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12 Jun 2018 Probability

A prime number is randomly picked from list of prime numbers less than 70 , what is probability that one of its digit will be 7?

OPtion

1) 5/17
2) 5/18
3) 4/19
4) 5/19
5) 6/19
6) 7/18
7) 7/17
8) 7/19
9) 6/17
10) None of these

Solution

Total number of prime numbers less than 70 = 19 => 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67
Number of positive outcomes i.e. number where at least one of its digit is 7 = 5

Probability = 5/19

Correct Option: 4 Best Solution (6)