Question
How many numbers are there between 99 and 1000 such that
the digit 8 occupies the units place?Solution
These are of the form _ _ 8, where the last digit is 8.
So the units digit = 8.
Now, the hundreds digit can range from 1 to 9 (because it's a 3-digit number).
The tens digit can range from 0 to 9.
- Hundreds digit: 1 to 9 → 9 choices
- Tens digit: 0 to 9 → 10 choices
- Units digit: fixed as 8 → 1 choice
So, total number of such numbers = 9 x 10 x 1 = 90
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