How many numbers from 100 to 999 have exactly one zero digit
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Answer:
180.
Step-by-step explanation:
100 contains 2 zero digits.
101 - 109 have 9 numbers, 110 to 200 have 11 numbers
so for 101 to 200 its 20 numbers
Its also 20 for 201 to 300 and for all sets of 100 up to 900.
- that is 7 * 20 = 140 numbers
Finally from 901 to 999 we have 18.
Total = 20 + 140 + 18
= 2 + 20 + 140 + 18
= 180.