MathDB
Problems
Contests
National and Regional Contests
USA Contests
MAA AMC
AMC 12/AHSME
1958 AMC 12/AHSME
24
24
Part of
1958 AMC 12/AHSME
Problems
(1)
Average Rate
Source:
6/13/2009
A man travels
m
m
m
feet due north at
2
2
2
minutes per mile. He returns due south to his starting point at
2
2
2
miles per minute. The average rate in miles per hour for the entire trip is:
<
s
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b
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>
(
A
)
<
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p
a
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>
75
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>
(
B
)
<
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>
48
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>
(
C
)
<
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45
<
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(
D
)
<
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24
<
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−
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>
(
E
)
<
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>
impossible to determine without knowing the value of
m
<span class='latex-bold'>(A)</span>\ 75\qquad <span class='latex-bold'>(B)</span>\ 48\qquad <span class='latex-bold'>(C)</span>\ 45\qquad <span class='latex-bold'>(D)</span>\ 24\qquad\\ <span class='latex-bold'>(E)</span>\ \text{impossible to determine without knowing the value of }{m}
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(
A
)
<
/
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p
an
>
75
<
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a
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=
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x
−
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>
(
B
)
<
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>
48
<
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−
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>
(
C
)
<
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>
45
<
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x
−
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>
(
D
)
<
/
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p
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>
24
<
s
p
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a
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=
′
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a
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x
−
b
o
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′
>
(
E
)
<
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p
an
>
impossible to determine without knowing the value of
m
rate problems