Difference between revisions of "2000 AMC 12 Problems"
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== Problem 16 == | == Problem 16 == | ||
+ | |||
+ | A checkerboard of <math>13</math> rows and <math>17</math> columns has a number written in each square, beginning in the upper left corner, so that the first row is numbered <math>1,2,\ldots,17</math>, the second row <math>18,19,\ldots,34</math>, and so on down the board. If the board is renumbered so that the left column, top to bottom, is <math>1,2,\ldots,13,</math>, the second column <math>14,15,\ldots,26</math> and so on across the board, some squares have the same numbers in both numbering systems. Find the sum of the numbers in these squares (under either system). | ||
+ | |||
+ | <math>\text {(A)}\ 222 \qquad \text {(B)}\ 333\qquad \text {(C)}\ 444 \qquad \text {(D)}\ 555 \qquad \text {(E)}\ 666</math> | ||
[[2000 AMC 12 Problems/Problem 16|Solution]] | [[2000 AMC 12 Problems/Problem 16|Solution]] |
Revision as of 20:06, 31 January 2009
Contents
- 1 Problem 1
- 2 Problem 2
- 3 Problem 3
- 4 Problem 4
- 5 Problem 5
- 6 Problem 6
- 7 Problem 7
- 8 Problem 8
- 9 Problem 9
- 10 Problem 10
- 11 Problem 11
- 12 Problem 12
- 13 Problem 13
- 14 Problem 14
- 15 Problem 15
- 16 Problem 16
- 17 Problem 17
- 18 Problem 18
- 19 Problem 19
- 20 Problem 20
- 21 Problem 21
- 22 Problem 22
- 23 Problem 23
- 24 Problem 24
- 25 Problem 25
- 26 See also
Problem 1
In the year , the United States will host the International Mathematical Olympiad. Let
and
be distinct positive integers such that the product
. What is the largest possible value of the sum
?
Problem 2
Problem 3
Each day, Jenny ate of the jellybeans that were in her jar at the beginning of that day. At the end of the second day,
remained. How many jellybeans were in the jar originally?
Problem 4
The Fibonacci sequence starts with two 1s, and each term afterwards is the sum of its two predecessors. Which one of the ten digits is the last to appear in the units position of a number in the Fibonacci sequence?
Problem 5
If where
then
Problem 6
Two different prime numbers between and
are chosen. When their sum is subtracted from their product, which of the following numbers could be obtained?
Problem 7
How many positive integers have the property that
is a positive integer?
Problem 8
Figures ,
,
, and
consist of
,
,
, and
non-overlapping squares. If the pattern continued, how many non-overlapping squares would there be in figure
?
Problem 9
Mrs. Walter gave an exam in a mathematics class of five students. She entered the scores in random order into a spreadsheet, which recalculated the class average after each score was entered. Mrs. Walter noticed that after each score was entered, the average was always an integer. The scores (listed in ascending order) were 71,76,80,82, and 91. What was the last score Mrs. Walters entered?
Problem 10
The point is reflected in the
-plane, then its image
is rotated by
about the
-axis to produce
, and finally,
is translated by 5 units in the positive-
direction to produce
. What are the coordinates of
?
Problem 11
Two non-zero real numbers, and
satisfy
. Which of the following is a possible value of
?
Problem 12
Let A, M, and C be nonnegative integers such that . What is the maximum value of
+
+
+
?
Problem 13
One morning each member of Angela’s family drank an 8-ounce mixture of coffee with milk. The amounts of coffee and milk varied from cup to cup, but were never zero. Angela drank a quarter of the total amount of milk and a sixth of the total amount of coffee. How many people are in the family?
Problem 14
When the mean, median, and mode of the list
are arranged in increasing order, they form a non-constant arithmetic progression. What is the sum of all possible real values of ?
Problem 15
Let be a function for which
. Find the sum of all values of
for which
.
Problem 16
A checkerboard of rows and
columns has a number written in each square, beginning in the upper left corner, so that the first row is numbered
, the second row
, and so on down the board. If the board is renumbered so that the left column, top to bottom, is
, the second column
and so on across the board, some squares have the same numbers in both numbering systems. Find the sum of the numbers in these squares (under either system).
Problem 17
Problem 18
Problem 19
Problem 20
Problem 21
Through a point on the hypotenuse of a right triangle, lines are drawn parallel to the legs of the triangle so that the triangle is divided into a square and two smaller right triangles. The area of one of the two small right triangles is times the area of the square. The ratio of the area of the other small right triangle to the area of the square is
Problem 22
The graph below shows a portion of the curve defined by the quartic polynomial . Which of the following is the smallest?
Problem 23
Professor Gamble buys a lottery ticket, which requires that he pick six different integers from through
, inclusive. He chooses his numbers so that the sum of the base-ten logarithms of his six numbers is an integer. It so happens that the integers on the winning ticket have the same property— the sum of the base-ten logarithms is an integer. What is the probability that Professor Gamble holds the winning ticket?
Problem 24
If circular arcs and
have centers at
and
, respectively, then there exists a circle tangent to both
and
, and to
. If the length of
is
, then the circumference of the circle is
Problem 25
Eight congruent equilateral triangles, each of a different color, are used to construct a regular octahedron. How many distinguishable ways are there to construct the octahedron? (Two colored octahedrons are distinguishable if neither can be rotated to look just like the other.)
![[asy] import three; import math; unitsize(1.5cm); currentprojection=orthographic(2,0.2,1); triple A=(0,0,1); triple B=(sqrt(2)/2,sqrt(2)/2,0); triple C=(sqrt(2)/2,-sqrt(2)/2,0); triple D=(-sqrt(2)/2,-sqrt(2)/2,0); triple E=(-sqrt(2)/2,sqrt(2)/2,0); triple F=(0,0,-1); draw(A--B--E--cycle); draw(A--C--D--cycle); draw(F--C--B--cycle); draw(F--D--E--cycle,dotted+linewidth(0.7)); [/asy]](http://latex.artofproblemsolving.com/7/d/1/7d13f21ea69c61ec44e671434db41a0bdedb8189.png)