Difference between revisions of "Mock AIME 2 Pre 2005/Problems"
(Again, just copied for now) |
5849206328x (talk | contribs) |
||
Line 1: | Line 1: | ||
+ | ==Problem 1== | ||
− | + | Compute the largest integer <math>k</math> such that <math>2004^k</math> divides <math>2004!</math>. | |
− | 2 | + | ==Problem 2== |
− | + | <math>x</math> is a real number with the property that <math>x + \frac{1}{x} = 3</math>. Let <math>S_m = x^m + \frac{1}{x^m}</math>. Determine the value of <math>S_7</math>. | |
− | + | ==Problem 3== | |
− | + | In a box, there are <math>4</math> green balls, <math>4</math> blue balls, <math>2</math> red balls, a brown ball, a white ball, and a black ball. These balls are randomly drawn out of the box one at a time (without replacement) until two of the same color have been removed. This process requires that at most <math>7</math> balls be removed. The probability that <math>7</math> balls are drawn can be expressed as <math>\frac{m}{n}</math>, where <math>m</math> and <math>n</math> are relatively prime positive integers. Compute <math>m + n</math>. | |
− | + | ==Problem 4== | |
− | + | Let <math>S := \{5^k | k \in \mathbb{Z}, 0 \le k \le 2004\}</math>. Given that <math>5^{2004}</math> has <math>1401</math> digits, how many elements of <math>S</math> begin with the digit <math>1</math>? | |
− | + | ==Problem 5== | |
− | < | + | Let <math>S</math> be the set of integers <math>n > 1</math> for which <math>\frac{1}{n} = 0.d_1d_2d_3d_4\dots</math>, an infinite decimal that has the property that <math>d_i = d_{i+12}</math> for all positive integers <math>i</math>. Given that <math>9901</math> is prime, how many positive integers are in <math>S</math>? (The <math>d_i</math> are digits.) |
− | + | ==Problem 6== | |
− | + | <math>ABC</math> is a scalene triangle. Points <math>D</math>, <math>E</math>, and <math>F</math> are selected on sides <math>\overline{BC}</math>, <math>\overline{CA}</math>, and <math>\overline{AB}</math> respectively. The cevians <math>\overline{AD}</math>, <math>\overline{BE}</math>, and <math>\overline{CF}</math> concur at point <math>P</math>. If the areas of triangles <math>AFP</math>, <math>FBP</math>, and <math>CEP</math> are <math>126</math>, <math>63</math>, and <math>24</math> respectively, then determine the area of triangle <math>ABC</math>. | |
− | + | ==Problem 7== | |
+ | Anders, Po-Ru, Reid, and Aaron are playing Bridge. After one hand, they notice that all of the cards of two suits are split between Reid and Po-Ru's hands. Let <math>N</math> denote the number of ways <math>13</math> cards can be dealt to each player such that this is the case. Determine the remainder obtained when <math>N</math> is divided by <math>1000</math>. (Bridge is a card game played with the standard <math>52-</math>card deck.) | ||
− | + | ==Problem 8== | |
− | + | Determine the remainder obtained when the expression | |
+ | <cmath>2004^{2003^{2002^{2001}}}</cmath> | ||
+ | is divided by <math>1000</math>. | ||
− | + | ==Problem 9== | |
− | < | + | Let |
+ | <cmath>\left(1 + x^3\right)\left(1 + 2x^{3^2}\right)\cdots\left(1 + 1997x^{3^{1997}}\right) = 1 + a_1x^{k_1} + a_2x^{k_2} + \cdots + a_mx^{k_m}</cmath> | ||
+ | where <math>a_i \neq 0</math> and <math>k_1 < k_2 < \cdots < k_m</math>. Determine the remainder obtained when <math>a_{1997}</math> is divided by <math>1000</math>. | ||
− | + | ==Problem 10== | |
− | + | <math>ABCDE</math> is a cyclic pentagon with <math>BC = CD = DE</math>. The diagonals <math>\overline{AC}</math> and <math>\overline{BE}</math> intersect at <math>M</math>. <math>N</math> is the foot of the altitude from <math>M</math> to <math>\overline{AB}</math>. We have <math>MA = 25</math>, <math>MD = 113</math>, and <math>MN = 15</math>. [<math>ABE</math>] can be expressed as <math>\frac{m}{n}</math> where <math>m</math> and <math>n</math> are relatively prime positive integers. Determine the remainder obtained when <math>m+n</math> is divided by <math>1000</math>. | |
− | + | ==Problem 11== | |
− | < | + | <math>\alpha</math>, <math>\beta</math>, and <math>\gamma</math> are the roots of <math>x(x-200)(4x+1) = 1</math>. Let |
+ | <cmath>\omega = \tan^{-1}(\alpha) + \tan^{-1}(\beta) + \tan^{-1}(\gamma).</cmath> | ||
+ | The value of <math>\tan(\omega)</math> can be written as <math>\frac{m}{n}</math> where <math>m</math> and <math>n</math> are relatively prime positive integers. Determine the value of <math>m + n</math>. | ||
− | + | ==Problem 12== | |
− | + | <math>ABCD</math> is a cyclic quadrilateral with <math>AB = 8</math>, <math>BC = 4</math>, <math>CD = 1</math>, and <math>DA = 7</math>. Let <math>O</math> and <math>P</math> denote the circumcenter and intersection of <math>AC</math> and <math>BD</math> respectively. The value of <math>OP^2</math> can be expressed as <math>\frac{m}{n}</math>, where <math>m</math> and <math>n</math> are relatively prime positive integers. Determine the remainder obtained when <math>m+n</math> is divided by <math>1000</math>. | |
− | + | ==Problem 13== | |
+ | <math>P(x)</math> is the polynomial of minimal degree that satisfies | ||
+ | <cmath>P(k) = \frac{1}{k(k+1)}</cmath> | ||
+ | for <math>k = 1, 2, 3, \dots, 10</math>. The value of <math>P(11)</math> can be written as <math>-\frac{m}{n}</math>, where <math>m</math> and <math>n</math> are relatively prime positive integers. Determine <math>m+n</math>. | ||
+ | |||
+ | ==Problem 14== | ||
+ | |||
+ | <math>3</math> Elm trees, <math>4</math> Dogwood trees, and <math>5</math> Oak trees are to be planted in a line in front of a library such that | ||
+ | <cmath>\begin{eqnarray*} | ||
+ | \text{i)} & \text{No two Elm trees are next to each other.} \hspace{6 mm} \\ | ||
+ | \text{ii)} & \text{No Dogwood tree is adjacent to an Oak tree.} \\ | ||
+ | \text{iii)} & \text{All of the trees are planted.} \hspace{27 mm} | ||
+ | \end{eqnarray*}</cmath> | ||
How many ways can the trees be situated in this manner? | How many ways can the trees be situated in this manner? | ||
− | 15 | + | ==Problem 15== |
− | |||
− | |||
− | can be expressed as \frac{m}{n} where m and n are relatively prime positive integers. Determine m + n. | + | In triangle <math>ABC</math>, we have <math>BC = 13</math>, <math>CA = 37</math>, and <math>AB = 40</math>. Points <math>D</math>, <math>E</math>, and <math>F</math> are selected on <math>\overline{BC}</math>, <math>\overline{CA}</math>, and <math>\overline{AB}</math> respectively such that <math>\overline{AD}</math>, <math>\overline{BE}</math>, and <math>\overline{CF}</math> concur at the circumcenter of <math>ABC</math>. The value of |
+ | <cmath>\frac{1}{AD} + \frac{1}{BE} + \frac{1}{CF}</cmath> | ||
+ | can be expressed as <math>\frac{m}{n}</math> where <math>m</math> and <math>n</math> are relatively prime positive integers. Determine <math>m + n</math>. |
Latest revision as of 14:23, 11 November 2009
Contents
Problem 1
Compute the largest integer such that divides .
Problem 2
is a real number with the property that . Let . Determine the value of .
Problem 3
In a box, there are green balls, blue balls, red balls, a brown ball, a white ball, and a black ball. These balls are randomly drawn out of the box one at a time (without replacement) until two of the same color have been removed. This process requires that at most balls be removed. The probability that balls are drawn can be expressed as , where and are relatively prime positive integers. Compute .
Problem 4
Let . Given that has digits, how many elements of begin with the digit ?
Problem 5
Let be the set of integers for which , an infinite decimal that has the property that for all positive integers . Given that is prime, how many positive integers are in ? (The are digits.)
Problem 6
is a scalene triangle. Points , , and are selected on sides , , and respectively. The cevians , , and concur at point . If the areas of triangles , , and are , , and respectively, then determine the area of triangle .
Problem 7
Anders, Po-Ru, Reid, and Aaron are playing Bridge. After one hand, they notice that all of the cards of two suits are split between Reid and Po-Ru's hands. Let denote the number of ways cards can be dealt to each player such that this is the case. Determine the remainder obtained when is divided by . (Bridge is a card game played with the standard card deck.)
Problem 8
Determine the remainder obtained when the expression is divided by .
Problem 9
Let where and . Determine the remainder obtained when is divided by .
Problem 10
is a cyclic pentagon with . The diagonals and intersect at . is the foot of the altitude from to . We have , , and . [] can be expressed as where and are relatively prime positive integers. Determine the remainder obtained when is divided by .
Problem 11
, , and are the roots of . Let The value of can be written as where and are relatively prime positive integers. Determine the value of .
Problem 12
is a cyclic quadrilateral with , , , and . Let and denote the circumcenter and intersection of and respectively. The value of can be expressed as , where and are relatively prime positive integers. Determine the remainder obtained when is divided by .
Problem 13
is the polynomial of minimal degree that satisfies for . The value of can be written as , where and are relatively prime positive integers. Determine .
Problem 14
Elm trees, Dogwood trees, and Oak trees are to be planted in a line in front of a library such that How many ways can the trees be situated in this manner?
Problem 15
In triangle , we have , , and . Points , , and are selected on , , and respectively such that , , and concur at the circumcenter of . The value of can be expressed as where and are relatively prime positive integers. Determine .