1981 AMC 12 Problem 4
Attempt Problem 4 of the 1981 AMC 12 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 1981 AMC 12 solutions, or check the answer key.
All problems are used with official legal permission of the Mathematical Association of America (MAA).
4.
If three times the larger of two numbers is four times the smaller and the difference between the numbers is then the larger of the two numbers is
Answer: C
Small hint:
Let and denote the larger and smaller numbers
Big hint:
Use together with
Solution:
The relation gives Thus so
Therefore, the correct answer is C.
Problem 4 in other years
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