You are hand-numbering the pages of a report. If there are 238 numbered pages, how many digits will you write?
The numnered pages will have pages 1 through 9 with one digit each 10 through 99 with 2 digits each 100 through 238 with 3 digits each
Yeah, I figured that, but I'm stuck on the next parts. would the answer be 601 digits, 605 digits, or 606 digits then?
There are 9 pages from 1 to 9 How many pages from 10 to 99? How many pages from 100 to 238?
Look at pages 10 through 99. Subtract 9 from each number, it's as if it were pages 1 through 90, which is 90 pages.
Now look at pages 100 through 238, subtract 99 from each number, so it's as if it were pages 1 through 139, so there are 139 pages.
But wouldn't there be 91 digits between 10 and 99, because you count 10?
I was counting numbers, not digits. Digits is the next step.
I mean't numbers, my bad. But wouldn't there still be 91 numbers between 10-99?
You have 9 1-digit pages, 90 2-digit pages, and 139 3-digit pages
So then the answer would be 606 digits?
There are 90 2-digit numbers from 10 to 99. Think of it this way. All numbers from 1 to 100 are obviously 100 numbers. How many of the 100 numbers are 2-digit numbers? 100 is a 3-digit number. 1 - 9 are 9 1-digit number, so 100 - 1 - 9 = 90 2-digit numbers.
Yes, 9 x 1 + 90 x 2 + 139 x 3 = 606
Thank you! :)
wlcm
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