## The intricacies of card shuffling will be explored in the next colloquium

**Title:**Card Shuffling 101**Speaker:**Dr. Darin Stephenson, Hope College Mathematics Department**When/Where:**4:00 pm, Thur. Oct 25 in Schaap 1000

**Abstract:** We discuss the physical process of card shuffling (by various methods) and ways in which these processes can be modeled mathematically. Interesting mathematical questions include “How many shuffles are required to sufficiently ‘mix up’ a deck of cards?” and “How many shuffles will it take to return a deck of cards to its original ordering?” We will also discuss ways various people have exploited the mathematics of card shuffling to cheat at cards or perform card tricks. We will develop the necessary mathematical background relating to permutations and randomness, and explain some other real-world applications of these mathematical notions.

## MATH Challenge

The 2018 Michigan Autumn Take Home Challenge (or MATH Challenge) will take place on the morning (9:30am – 12:30pm) of Saturday, November 3 this year. Teams of two or three students take a three-hour exam consisting of ten interesting problems dealing with topics and concepts found in the undergraduate mathematics curriculum. Each team takes the exam at their home campus under the supervision of a faculty advisor.

The department pays the registration fee for each team and will provide lunch to participants afterwards. The sign-up deadline is Monday, October 22 at 5:00 p.m. Interested students can sign up by sending Prof. Cinzori an email at cinzori@hope.edu.

A group of students may sign up as a team. Individual students are also encouraged to sign up; they will be assigned to a team on the day of the competition. For more information, please talk with any member of the Mathematics Department or visit the MATH Challenge website where you can also view old copies of the exam.

## U of M Biostatistics Prospective Student Day

The Department of Biostatistics at the University of Michigan will hold a Prospective Student Information Day on Saturday, November 10, 2018. The purpose of this event is to provide information to students who may be interested in graduate study in biostatistics. They expect attendees to be undergraduate and masters students who have identified biostatistics as their interest area, as well as students who are completing an undergraduate degree in math, statistics, biology, or some related discipline, and have not yet decided on their future plans.

At the event, presentations by students and faculty will focus on what biostatistics is and what biostatisticians do, on the job opportunities in biostatistics, and on the admissions and financial support opportunities at the University.

For more information, take a look at their flyer or visit their website (where you can also register).

## Problem Solvers of the Fortnight

Congratulations to Holly Denouden, Ce Gao, Zheng Qu, Cole Persch, Hugh Thiel, and Yizhe Zhang – all of whom correctly solved the Problem of the Fortnight in the last issue of America’s premiere fortnightly mathematics department blogosphere news post.

## Problem of the Fortnight

Tommy Turtle and a Sammy Snail are at the corner of a cubical aquarium with side length 3 ft. “Wanna race to the opposite corner?” asks Tommy. “Well . . . I . . . suppose . . . some . . . exercise . . . might . . . be . . . nice,” Sammy replies. Tommy can swim through the interior of the cube at a rate of 6 ft/min, while Sammy has to stick to the sides but can slide along at a rate of 2 ft/min. If they take off at the same time, how long, to the nearest tenth of a second, does Tommy have to wait for Sammy at the opposite corner (assuming, of course, they both go on their respective shortest routes)?

Write your solution on a cubical aquarium (of any size) and drop it in the Problem of the Fortnight slot outside Professor Mark Pearson’s office, room 212 in The Werf, by 3:00 p.m. on Friday, October 19. As always, be sure to include your name and the name(s) of your math professor(s) – e.g. Ellie DeLuits, Professor N. Candessent – on your solution. Good luck and have fun!