Question

How many 7 digit phone numbers can be created if the first digit cannot be a zero, and the lastnumber must be an odd number?

Answer 1

Given:

Number of digits = 7

The first digit cannot be zero

Last number = odd number

The possible numbers between other than zero is 9

and there are 5 odd numbers.

Hence, the number of possible combinations is:

`\begin{gathered} =\text{ 9 }*\text{ 10 }*\text{ 10 }*\text{ 10 }*\text{ 10 }*\text{ 10 }*\text{ 5} \\ =\text{ 4500000} \end{gathered}`

Answer: Option A