The pages of a book are numbered consecutively 1,2,3 4 and so on. No pages are missing. If in the page numbers the digit 3 occurs exactly 99 times, what is the number of the last page
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3 occurs between 30 & 39 - 11 times. from 1 to 29 - 3 times & 40 to 99 - 6 times.
So 3 occurs 20 times in 100.
UP to 299 - 3 occurs : 60 times
3 occurs 11 times each from 300 to 309, and from 310 to 319 and frm 320 to 329.
So Up to 329 , 3 occurs 93 times
330,331,332,333,
So up to page 332, the occurrance of 3 is 99 times.
So 3 occurs 20 times in 100.
UP to 299 - 3 occurs : 60 times
3 occurs 11 times each from 300 to 309, and from 310 to 319 and frm 320 to 329.
So Up to 329 , 3 occurs 93 times
330,331,332,333,
So up to page 332, the occurrance of 3 is 99 times.
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