1953 AMC 12 Problem 31
Attempt Problem 31 of the 1953 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 1953 AMC 12 solutions, or check the answer key.
All problems are used with official legal permission of the Mathematical Association of America (MAA).
31.
The rails on a railroad are feet long. As the train passes over the point where the rails are joined, there is an audible click. The speed of the train in miles per hour is approximately the number of clicks heard in:
seconds
minutes
minutes
minutes
none of these
Answer: A
Small Hint:
Convert one mile per hour to feet per second, then divide by feet per click
Big Hint:
Find the time interval for which the click count is approximately the numerical speed in miles per hour
Solution:
A speed of miles per hour is feet per second. Since each click represents feet, the click rate is clicks per second. In seconds, the number of clicks is The closest listed interval is seconds.
Thus, the correct answer is A.
Problem 31 in Other Years
1950 AMC 12 · 1951 AMC 12 · 1952 AMC 12 · 1954 AMC 12 · 1955 AMC 12 · 1956 AMC 12 · 1957 AMC 12 · 1958 AMC 12 · 1959 AMC 12 · 1960 AMC 12 · 1961 AMC 12 · 1962 AMC 12 · 1963 AMC 12 · 1964 AMC 12 · 1965 AMC 12 · 1966 AMC 12 · 1967 AMC 12 · 1968 AMC 12 · 1969 AMC 12 · 1970 AMC 12 · 1971 AMC 12 · 1972 AMC 12 · 1973 AMC 12