1985 AMC 8 Problem 25
Below is the professionally curated solution for Problem 25 of the 1985 AMC 8, from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 1985 AMC 8 solutions, or check the answer key.
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Difficulty rating: 1140
25.
Five cards are lying on a table. Each card has a letter on one side and a whole number on the other side. The visible faces show and Jane said, "If a vowel is on one side of any card, then an even number is on the other side." Mary showed Jane was wrong by turning over one card. Which card did Mary turn over?
Solution:
To show the rule "a vowel forces an even number" is false, Mary needs a card with a vowel on one side and an odd number on the other. No card shows a vowel, since and are consonants.
The only card showing an odd number is Turning it over reveals a vowel, which contradicts Jane's claim.
Thus, the correct answer is A .
Problem 25 in Other Years
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