Difference between revisions of "1968 AHSME Problems/Problem 33"
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== See also == | == See also == | ||
− | {{AHSME box|year=1968|num-b=32|num-a=34}} | + | {{AHSME 35p box|year=1968|num-b=32|num-a=34}} |
[[Category: Intermediate Algebra Problems]] | [[Category: Intermediate Algebra Problems]] | ||
{{MAA Notice}} | {{MAA Notice}} |
Latest revision as of 01:53, 16 August 2023
Problem
A number has three digits when expressed in base
. When
is expressed in base
the digits are reversed. Then the middle digit is:
Solution
Call the number in base 7.
Then, . (Breaking down the number in base-form).
After combining like terms and moving the variables around,
,
. This shows that
is a multiple of 8 (we only have to find the middle digit under one of the bases). Thus,
(since 8>6, the largest digit in base 7).
Select as our answer.
~hastapasta
See also
1968 AHSC (Problems • Answer Key • Resources) | ||
Preceded by Problem 32 |
Followed by Problem 34 | |
1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 • 16 • 17 • 18 • 19 • 20 • 21 • 22 • 23 • 24 • 25 • 26 • 27 • 28 • 29 • 30 • 31 • 32 • 33 • 34 • 35 | ||
All AHSME Problems and Solutions |
The problems on this page are copyrighted by the Mathematical Association of America's American Mathematics Competitions.