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23 votes
When the integers 1 to 100 inclusive are written, what digit is the fewest numbers of the time

User Yngvar Kristiansen
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1 Answer

23 votes
23 votes

Answer: 0

Explanation:

First you do 1 through 9,

then 10 through 19,

then 20 through 29.

You have one set of 9 numbers,

1-9, and 9 sets of ten numbers such as 20-29. Looking at the tens digit, 1 is used 10 times for 10-19, 2 is used 10 times for 20-29, 3 is used 10 times, etc.

However, 0 is not used as a tens digit except in the number 100.

If the digit is not 0, then it occurs 10 times as a ten digit.

In addition, it occurs once in each set of ten, for a total of 20 times. For example, consider 6. It occurs ten times in 60-69, and then another ten times as 6, 16, 26, 36, etc., for a total of 20.

O occurs as 10, 20, 30, 40, 50, etc plus an extra 0 in 100, for a total of 11 times.

User Bob Whiteman
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