Question

A credit card contains 16 digits between 0 and 9. However, only 300 million numbers are valid. If a number is entered randomly, what is the probability that it is a valid number

Answer 1

The probability that a randomly entered number is valid will be 0.00000003

Step-by-step explanation

From 0 to 9, there are total 10 digits and the credit card number should be of 16 digits.

So, the total possible 16 digit credit card numbers
`=10^1^6`

Now, the valid numbers are only 300 millions
`i.e`
`3*10^8`

Thus, the probability that a randomly entered number is valid
`= (3*10^8)/(10^1^6)= 3*10^-^8 = 0.00000003`