How many three digit numbers contain the digit 2?

Answer 1

100-199 has 19 numbers

200-299 has 100 numbers

300-399 has 19 numbers

400-499 has 19 numbers

500-599 has 19 numbers

600-699 has 19 numbers

700-799 has 19 numbers

800-899 has 19 numbers

900-999 has 19 numbers

(8x19)+100 = 152 + 100 = 252

252 three digit numbers contain the digit 2

Answer 2

There are several ways to answer this. I think this is the easiest:

Count the number of three-digit numbers:

The first digit can be 1-9; the second and third digits can be 0-9. So, there are 9 choices for the first digit and 10 choices for the second and third digits. This gives you

9 x 10 x 10 = 900 three-digit numbers. Right?

Then count the number of three-digit numbers that do NOT contain the digit 2. This is done similarly! Try it!

Now, if you think about it, the difference between these two quantities IS the number of three-digit numbers that DO contain a 2, which is what you wanted.

Answer 3

Ech separate Hundred contains 19 such digits, except the two-hundreds which contain a hundred. 8 x 19 = 152, plus 100 = 252

Answer 4

21