Question 334813: Pat has a collection of stickers for numbering pages in a scrapbook. Each sticker has 1 digit on it (0, 1, 2, 3, 4, 5, 6, 7, 8, or 9). Pat has twenty-two stickers that have "2" on them. Pat has plenty of the rest of the digits. If Pat starts at 1, how many pages can he number?
a. 22
b. 99
c. 112
d. 119
e. 199
Answer by Edwin McCravy(20060)   (Show Source):
You can put this solution on YOUR website!
It takes 20 2's for the UNITs' digits only of 02, 12, 22, 32, etc., thru 192.
That's because the digits I've colored red before the last 2's are the numbers
from 0 to 19, which is 20 2's needed for the UNITs' digits only.
It takes the remaining two 2's to make the ten's digits of 22 and 122.
So she uses her last 2 on page 192. But she won't need any more
2's till she gets to page 200, which she won't be able to number because
she will be out of 2's. So she can only number through page 199, choice e.
Edwin
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