Question

A computer randomly generates a 5-digit string using numbers between 0 and 9 inclusive. What is the probability that the first two digits in the string are a 4 and a 2 , in that order?

Answer 1

Answer: 0.01.

Explanation:

Given: A computer randomly generates a 5-digit string using numbers between 0 and 9 inclusive.

i.e. each place in 5 digit number has 10 choices.

Total ways to make such a number =
`10^5=100000`.

If the first two digits in the string are a 4 and a 2, in that order, then the number of ays to make this kind of number = 1 x 1 x 10 x 10 x 10 = 1000 [as 4 and 2 can be put on first and second place in 1 way ]

Now, the probability that the first two digits in the string are a 4 and a 2 , in that order =
`(1000)/(100000)=(1)/(100)=0.01`

Hence, the probability that the first two digits in the string are a 4 and a 2 , in that order = 0.01.