SOLUTION: In a building all office doors were numbered, using plates containing one digit each (for example, when numbering office number 14 two plates were used, one with the number 1 and t

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: In a building all office doors were numbered, using plates containing one digit each (for example, when numbering office number 14 two plates were used, one with the number 1 and t      Log On


   



Question 1093255: In a building all office doors were numbered, using plates containing one digit each (for example, when numbering office number 14 two plates were used, one with the number 1 and the other with the number 4. If in total 35 plates were used, how many doors are there?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Doors 1 through 9 use +9+
plates
Doors 10 through 19 use +2%2A10+=+20+
plates
Doors 20 through 22 use +2%2A3+=+6+
plates
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Total plates used is +9+%2B+20+%2B+6+=+35+
The total number of doors is +22+