Problem Solving

The student lockers at Olympic High are numbered consecutively beginning with locker number 1. The plastic digits used to number the lockers cost two cents apiece. Thus, it costs two cents to label locker number 9 and four cents to label locker number 10. If it costs $137.94 to label all the lockers, how many lockers are there at the school?
A. 2001
B. 2010
C. 2100
D. 2726
E. 6897



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sanju09 wrote:The student lockers at Olympic High are numbered consecutively beginning with locker number 1. The plastic digits used to number the lockers cost two cents apiece. Thus, it costs two cents to label locker number 9 and four cents to label locker number 10. If it costs $137.94 to label all the lockers, how many lockers are there at the school?
A. 2001
B. 2010
C. 2100
D. 2726
E. 6897



[spoiler]https://www.gmatmaths.com[/spoiler]

9 -> [1 - 9] -> 2cents
90 -> [10-99] - 4 cents
999 -> [100-999] - 6 cents
x -> having 4 digits - 8 cents

So, 9*2+90*4+999*6+x*8 = 13794
=> x = 1002
So, total no. of lockers = 9+90+999+1002 = 999+1002 = 2001 A