Question

How many three digit numbers have a 2 as a tens digit??

Answer 1

90 numbers

Explanation:

Considering the stipulations from the question, the layout for the 3-digit number is:

`\underline{x}\:\underline{2}\:\underline{y}`

The hundreds digit,
`x`, can be any number from 1-9 inclusive, which contains 9 numbers.

The tens digit, 2, is fixed, as stipulated from the problem, and therefore may only be one number, 2.

The ones digit,
`y`, can be any number from 0-9 inclusive which gives 10 options.

Therefore, there are
`9\cdot 1\cdot 10=\boxed{90}` three digit numbers that have 2 as a tens digit.