2004 AMC 12B Problem 15
Below is the professionally curated solution for Problem 15 of the 2004 AMC 12B, from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2004 AMC 12B solutions, or check the answer key.
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Difficulty rating: 1510
15.
The two digits in Jack's age are the same as the digits in Bill's age, but in reverse order. In five years Jack will be twice as old as Bill will be then. What is the difference in their current ages?
Solution:
Let Jack be and Bill be Then so Testing digits, only works, so Jack is and Bill is The difference is
Thus, the correct answer is B.
Problem 15 in Other Years
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