Riddler Classic – 8/9/2019

This week’s Riddler Classic is about building bridges of a sort.

In your yard, there is a circular pond with radius one yard. (I can hear the cringes of all the science people from here.) You have a collection of thin planks, each of radius one yard. The question is to find the minimum number of planks required to cover the center of the pond. The rule is that the planks can only touch the edge of the pond or other planks. The puzzle does not explicitly state that no adhesives or hardware are allowed, but we can assume that violates the spirit of the puzzle.

The answer is below.

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Riddler Express – 6/28/2019

This week’s Riddler Express is a probability question. You have two buckets, 50 red ping-pong balls, and 50 blue ping-pong balls. You friend will pick one bucket at random, and then one ping-pong ball in that bucket at random. The question is how to arrange the ping-pong balls so the probability of your friend picking a red ball is as high as possible. The only additional rule is that there must be at least one ball in each bucket.

The solution is below.

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Up and Out a Rabbit Hole

One of the features of being an educator is having long periods of time with few scholastic responsibilities. Part of this time is used for planning the next academic year. When researching software for video editing on Linux, I fell down a rabbit hole of distraction. It took me a while to catch that I was at the bottom, and once I did, I could see the reasons for being there. I have taken the time to refocus on my priorities, and I am ready move forward.

My academic years are full of pressure, and that pressure is off right now. This year has been a marathon run at a sprint pace. Now that I am off contract, I have no deadlines to worry about until July. That has let me sleep eight hours every night. Finally, I have the energy to reflect about this past year and plan for next year. The downside to freedom is that I am easily distracted.

While researching software for video editing on Linux, I came across a channel with Linux tips and reviews. After watching the videos, I had a dangerous thought: I can do that too! If I was going to work on creating mathematics videos, why not start a Linux tutorial channel and make some money? Through my comments on a different channel, I got positive feedback on my past videos. That was enough to seed me spiraling down a distraction drain. After a couple days of working late and setting up computer hardware and software, I realized I was forgetting quite a few important things. My family being the first item of that list.

To be honest, I have always had the desire to be known as an intelligent person. It has never been good enough to just show up and be 90% as good as the best person. In addition, if someone is talented in the same area as me, I cannot let them have all the glory. I have always had to say, “Look at me too!” A couple of months ago, I realized that this is a manifestation of low self-esteem. Even though I know the source of my issues, I am still unable to stop myself in time.

For the future, I must work to remember what I need to accomplish. The first is to become a more effective teacher and educator. The second is to have fun learning new things. My message must be, “This is fun and you can do it too.”

There are three steps I will follow going forward. The first is to disengage with the sources promising false fame. More on this later. Second is to move up the media production difficulty ladder one rung at a time. Maybe do some writing before working up to a podcast. Don’t jump into constructing a video production studio right away. The third is to prioritize and calm the chaos around me. I made some good progress this week while building a workspace. I need to keep ordering my environment so I can get to the next academic year ready to succeed, not play catch-up.

The luxury of time is mine for the rest of this month. My intention is to use that time to develop as and educator. It was temping to start a side adventure and accumulate fame as a technology tutor. It took a few days of feverishly doing the wrong jobs to realize what the right jobs are. Sharing a joy of learning is my mission. To accomplish this mission, I must constantly remind myself that a know-it-all cannot be a true learner.

Riddler Express – 1/11/2019

This week’s Riddler Express is about finding small factors of large numbers. The goal is to find the missing digit of the number below with factors all less than 100.

530,131,801,762,787,739,802,889,792,754,109,70_,139,358,547,710,066,257,652,050,346, …294,484,433,323,974,747,960,297,803,292,989,236,183,040,000,000,000

It turns out that Python is well equipped to handle a problem like this. The solution follows.

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Riddler Express – 1/4/2019

This weeks Riddler Express is deceptively difficult. I say that I fell for the simple solution and did not catch it until it was too late.

The problem starts with an encyclopedia with 20 volumes. Each volume is 2 cm thick, and has a cover that is 2 mm thick. A bookworm wiggles to page one of volume one. The worm then eats through each volume to the last page of volume 20. The problem is to find how far the worm travels.

The solution is below.

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Riddler Express – 12/21/2018

This week’s Riddler Express is about Santa hitching up the reindeer. He does not remember the order of the reindeer, with the exception of that showoff Rudolph. The reindeer can tell Santa if they are in the correct position, but cannot tell any more information.

Santa’s solution is to try the reindeer one at a time at the front of the sleigh until he gets the correct one. Then, he moves on to the next position. It takes Santa one minute to hitch up one reindeer. The question is to find out how long to expect this process to take. The answer is below.

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Riddler Classic – 12/21/2018

This week’s Riddler Classic is about using probability to estimate the length of a playlist.

Santa’s elves are working in the workshop and listening to 100 songs each shift. About half of the time, there is at least one song that is repeated. The problem is to use the information above to find the length of Santa’s playlist.

The solution is below.

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