MathDB
2022 BmMT Team Round - Berkley mini Math Tournament Spring

Source:

August 31, 2022
bmmtalgebrageometrycombinatoricsnumber theorygraphing lines

Problem Statement

p1. If x2=7x^2 = 7, what is x4+x2+1x^4 + x^2 + 1?
p2. Richard and Alex are competing in a 150150-meter race. If Richard runs at a constant speed of 55 meters per second and Alex runs at a constant speed of 33 meters per second, how many more seconds does it take for Alex to finish the race?
p3. David and Emma are playing a game with a chest of 100100 gold coins. They alternate turns, taking one gold coin if the chest has an odd number of gold coins or taking exactly half of the gold coins if the chest has an even number of gold coins. The game ends when there are no more gold coins in the chest. If Emma goes first, how many gold coins does Emma have at the end?
p4. What is the only 33-digit perfect square whose digits are all different and whose units digit is 55?
p5. In regular pentagon ABCDEABCDE, let FF be the midpoint of AB\overline{AB}, GG be the midpoint of CD\overline{CD}, and HH be the midpoint of AE\overline{AE}. What is the measure of FGH\angle FGH in degrees?
p6. Water enters at the left end of a pipe at a rate of 11 liter per 3535 seconds. Some of the water exits the pipe through a leak in the middle. The rest of the water exits from the right end of the pipe at a rate of 11 liter per 3636 seconds. How many minutes does it take for the pipe to leak a liter of water?
p7. Carson wants to create a wire frame model of a right rectangular prism with a volume of 20222022 cubic centimeters, where strands of wire form the edges of the prism. He wants to use as much wire as possible. If Carson also wants the length, width, and height in centimeters to be distinct whole numbers, how many centimeters of wire does he need to create the prism?
p8. How many ways are there to fill the unit squares of a 3×53 \times 5 grid with the digits 11, 22, and 33 such that every pair of squares that share a side differ by exactly 11?
p9. In pentagon ABCDE, AB=54AB = 54, AE=45AE = 45, DE=18DE = 18, A=C=E\angle A = \angle C = \angle E, DD is on line segment BE\overline{BE}, and line BDBD bisects angle ABC\angle ABC, as shown in the diagram below. What is the perimeter of pentagon ABCDEABCDE? https://cdn.artofproblemsolving.com/attachments/2/0/7c25837bb10b128a1c7a292f6ce8ce3e64b292.png
p10. If xx and yy are nonzero real numbers such that 7x+8y=91\frac{7}{x} + \frac{8}{y} = 91 and 6x+10y=89\frac{6}{x} + \frac{10}{y} = 89, what is the value of x+yx + y?
p11. Hilda and Marianne play a game with a shued deck of 1010 cards, numbered from 11 to 1010. Hilda draws five cards, and Marianne picks up the five remaining cards. Hilda observes that she does not have any pair of consecutive cards - that is, no two cards have numbers that differ by exactly 11. Additionally, the sum of the numbers on Hilda's cards is 11 less than the sum of the numbers on Marianne's cards. Marianne has exactly one pair of consecutive cards - what is the sum of this pair?
p12. Regular hexagon AUSTINAUSTIN has side length 22. Let MM be the midpoint of line segment ST\overline{ST}. What is the area of pentagon MINUSMINUS?
p13. At a collector's store, plushes are either small or large and cost a positive integer number of dollars. All small plushes cost the same price, and all large plushes cost the same price. Two small plushes cost exactly one dollar less than a large plush. During a shopping trip, Isaac buys some plushes from the store for 59 dollars. What is the smallest number of dollars that the small plush could not possibly cost?
p14. Four fair six-sided dice are rolled. What is the probability that the median of the four outcomes is 55?
p15. Suppose x1,x2,...,x2022x_1, x_2,..., x_{2022} is a sequence of real numbers such that: x1+x2=1x_1 + x_2 = 1 x2+x3=2x_2 + x_3 = 2 ...... x2021+x2022=2021x_{2021} + x_{2022} = 2021 If x1+x499+x999+x1501=222x_1 + x_{499} + x_{999} + x_{1501} = 222, then what is the value of x2022x_{2022}?
p16. A cone has radius 33 and height 44. An infinite number of spheres are placed in the cone in the following way: sphere C0C_0 is placed inside the cone such that it is tangent to the base of the cone and to the curved surface of the cone at more than one point, and for i1i \ge 1, sphere CiC_i is placed such that it is externally tangent to sphere Ci1C_{i-1} and internally tangent to more than one point of the curved surface of the cone. If ViV_i is the volume of sphere CiC_i, compute V0+V1+V2+...V_0 + V_1 + V_2 + ... . https://cdn.artofproblemsolving.com/attachments/b/4/b43e40bb0a5974dd9d656691c14b4ae268b5b5.png
p17. Call an ordered pair, (x,y)(x, y), relatable if xx and yy are positive integers where yy divides 36003600, xx divides yy and yx\frac{y}{x} is a prime number. For every relatable ordered pair, Leanne wrote down the positive difference of the two terms of the pair. What is the sum of the numbers she wrote down?
p18. Let r,sr, s, and tt be the three roots of P(x)=x39x9P(x) = x^3 - 9x - 9. Compute the value of (r3+r210r8)(s3+s210s8)(t3+t210t8)(r^3 + r^2 - 10r - 8)(s^3 + s^2 - 10s - 8)(t^3 + t^2 - 10t - 8).
p19. Compute the number of ways to color the digits 0,1,2,3,4,5,6,7,80, 1, 2, 3, 4, 5, 6, 7, 8 and 99 red, blue, or green such that: (a) every prime integer has at least one digit that is not blue, and (b) every composite integer has at least one digit that is not green.
Note that 00 is not composite. For example, since 1212 is composite, either the digit 11, the digit 22, or both must be not green.
p20. Pentagon ABCDEABCDE has AB=DE=4AB = DE = 4 and BC=CD=9BC = CD = 9 with ABC=CDE=90o\angle ABC = \angle CDE = 90^o, and there exists a circle tangent to all five sides of the pentagon. What is the length of segment AE\overline{AE}?
PS. You should use hide for answers. Collected [url=https://artofproblemsolving.com/community/c5h2760506p24143309]here.