2005 AMC 12A Problem 19
Below is the professionally curated solution for Problem 19 of the 2005 AMC 12A, from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2005 AMC 12A solutions, or check the answer key.
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Difficulty rating: 1950
19.
A faulty car odometer proceeds from digit to digit always skipping the digit regardless of position. For example, after traveling one mile the odometer changed from to If the odometer now reads how many miles has the car actually traveled?
Solution:
Because the odometer never displays a it uses only symbols and counts in base where its digits represent the base- digits
The reading therefore corresponds to in base which equals
Thus, the correct answer is B.
Problem 19 in Other Years
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