2003 AMC 12A Problem 12
Attempt Problem 12 of the 2003 AMC 12A below, then check your answer against the professionally curated solution from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2003 AMC 12A solutions, or check the answer key.
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12.
Sally has five red cards numbered through and four blue cards numbered through She stacks the cards so that the colors alternate and so that the number on each red card divides evenly into the number on each neighboring blue card. What is the sum of the numbers on the middle three cards?
Answer: E
Small hint:
Among the blue numbers the red divides only and the red divides only
Big hint:
Work inward from the forced ends and
Solution:
Since divides only and divides only among the two ends must be
Because divides only and the next card is and since divides only and the full stack is
The middle three cards are which sum to
Thus, the correct answer is E.
Problem 12 in other years
- 1950 AMC 12
- 1951 AMC 12
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