aniketb wrote:

A password of a computer used five digits where they are from 0 and 9. What is the probability that the password solely consists of prime numbers and zero?

A. 1/32

B. 1/16

C. 1/8

D. 2/5

E. 1/2

The total number of ways to select 5 digits to form a 5-digit password is 10^5. The number of ways to select the 5 digits that are either a prime (2, 3, 5, 7) or zero is 5^5. Therefore, the probability is 5^5/10^5 = (5/10)^5 = (1/2)^5 = 1/32.

Answer: A

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