2001 AMC 12 Problems/Problem 6
- The following problem is from both the 2001 AMC 12 #6 and 2001 AMC 10 #13, so both problems redirect to this page.
Problem
A telephone number has the form , where each letter represents
a different digit. The digits in each part of the number are in decreasing
order; that is,
,
, and
. Furthermore,
,
, and
are consecutive even digits;
,
,
, and
are consecutive odd
digits; and
. Find
.
Solution
We start by noting that there are letters, meaning there are
digits in total. Listing them all out, we have
. Clearly, the most restrictive condition is the consecutive odd digits.
Case 1: ,
,
, and
are
,
,
, and
respectively.
A cursory glance allows us to deduce that the smallest possible sum of
is
when
,
, and
are
,
, and
respectively, so this is out of the question.
Case 2: ,
,
, and
are
,
,
, and
respectively.
A cursory glance allows us to deduce the answer. Clearly, when
,
, and
are
,
, and
respectively,
is
when
,
, and
are
,
, and
respectively, giving us a final answer of
See Also
2001 AMC 12 (Problems • Answer Key • Resources) | |
Preceded by Problem 5 |
Followed by Problem 7 |
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 | |
All AMC 12 Problems and Solutions |
2001 AMC 10 (Problems • Answer Key • Resources) | ||
Preceded by Problem 12 |
Followed by Problem 14 | |
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 | ||
All AMC 10 Problems and Solutions |
The problems on this page are copyrighted by the Mathematical Association of America's American Mathematics Competitions.