MBA.Aspirant wrote:How many number of times will the digit '7' be written when listing the integers from 1 to 1000?
(a) 271
(b) 300
(c) 252
(d) 304
(e) 512
If we use 0 as a placeholder -- so that 007 represents 7, 072 represents 72, etc. -- then we need to count the number of times that 7 will appear among the 3-digit integers from 000 to 999, inclusive.
Total number of 3-digit integers from 000 to 999, inclusive = biggest - smallest + 1 = 999-000+1 = 1000.
Each of these 1000 integers includes 3 digits.
Thus, the total number of digit appearances = 3*1000 = 3000.
Among these 3000 digit appearances, each of the 10 digits will appear the same number of times.
Thus, the number of times that 7 will appear = 3000/10 = 300.
The correct answer is
B.
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