You have two buckets each with a capacity of an integer number of units. The buckets have no measuring marks, and it is impossible to tell how much is in a partially-filled bucket by looking. You have to work out a way to measure out a certain integer number of units of water by pouring water into and out of the buckets.
The classic version of this puzzle is with a three-unit bucket and a five-unit bucket with the object of measuring out four units of water.
The three scenarios to solve are:
1) The two buckets have capacities of three units and seven units. Measure out two units.
2) Six and seven. Measure out four.
3) Five and eight. Measure out four.
Submit your answer to Gene Wirchenko <email@example.com>. Your answer should be in the form of a proof. That means to show how your answer must be correct. The deadline is Wednesday, April 30, 2014 at noon Pacific Time. I will post the answer shortly after.
My second blog post was Business Miscommunication in the Job Hunt. I wrote about how it was not very nice of employers to not reply to job applicants.
Months later, with only a few bites and tired of not getting hired, I decided to bite the bullet and apply for an any job to keep the wolf from the door. I applied to a local company that has several locations of a food service franchise.
I was not hired, but I asked for some feedback and got some. It turned out the other applicants had specific experience. It also turned out that I had not disqualified myself. This was good to know as one can all-too-easily second-guess oneself on how one did in the interview.
(At the end of one programming job interview, I asked, that if I were not hired, if I could get some feedback on how I did. When I got an E-mail stating that I did not get the position, there was no feedback. I replied asking again, and I got no reply.)
There is another company in town with locations of the same franchise, and they advertised that week. I decided to try them. I arranged an interview with the general manager who thought I was acceptable but required that I meet the particular location manager. I did that, and I was hired.
I was treated coureously by both companies.
I wonder why the difference in behaviour between these two companies and most of the other companies that I have applied to. I think that it is because the business of the franchise is dealing with the general public and that they keep that in mind whenever dealing with people. What do you think?
(Why have I not identified the company? My manager asked me not to. Besides, I made my point here without having to identify the franchise.)
A little courtesy can go a long way.
Kari Maaren (recent blog post: “Kari Maaren Rules!”, her Website: http://karimaaren.com/) wrote a series of posts called “Kem’s Utterly Merciless Guide to Essay Writing” (http://kemthemerciless.blogspot.ca/). In the Wednesday, October 15, 2008 post (“I Am a Bad, Bad Person”), she opens with “I am going to post again properly. I swear.”
The issue: Normally, the “I swear.” would be taken as meaning that she promises she will “post again properly”. It could also mean that Kari swears (as in foul language), and as she does many a time in the guide, the “I swear.” is ambiguous.
(The guide is excellent. Kari did vent somewhat, but I think she had good reason to. I wish I had had her guide to read when I was in high school.)
Your sock drawer is quite a mess. You have eight black socks, seven white socks, two blue socks, and one weird striped sock. They are all indistinguishable in the dark. It is dark, and you want to select the least number of socks in each scenario.
1) The socks have been put into pairs though not necessarily matching pairs. How many pairs (no rematching allowed) do you need to select to be sure of getting at least two matching socks (which could be from different pairs)?
2) The socks are all loose. How many socks do you need to select to be sure of getting at least one matching pair?
3) Like #2, but now, you want two matching pairs.
Submit your answer to Gene Wirchenko <firstname.lastname@example.org>. Your answer should be in the form of a proof. That means to show how your answer must be correct. The deadline is Wednesday, April 23, 2014 at noon Pacific Time. I will post the answer shortly after.
I tutor a high-functioning autistic boy in mathematics. One of the biggest problems that I have with him is that he learned how to play aides. By playing dumb, he got them to do a bunch of the work for him. Back when he was doing basic arithmetic, this and guesses worked fairly well for him. Now that he trying to learn algebra, it does not work very well.
After I have presented new material to him and have given him a set of problems to work on, so often, the most useful thing that I can then do is to read something. I do keep an eye on how he is doing, but I am not active. Even then, he still tries to draw me into solving the problems.
He is slowly getting better, but he never will if I help him through every problem.
Sometimes, to help someone, you have to let him fail on his own.
MacLean’s magazine, 2014-02-17, p. 13, Barbara Amiel’s column “Dear Evan, In reply to your recent letter…”:
‘When he writes that I “cheaply toss[ed] out the notion” of his anti-Semistism–which I demonstrably did not–it’s unclear whether he is complaining that I cheaply refused to accuse him of anti-Semitism or that I did. “Tossed out” could go either way.’
The issue: “toss out” can mean to dispose of or to put forth.
The date and time can be expressed in the form “YY-MM-DD hh:mm” where each letter stands for a digit. (For example, as I write this, it is 14-03-27 14:38.) What is the earliest date/time where all ten digits are different?
You say that one really should use the full year? Fine by me. Expressing the date in ISO 8601 standard form–yes, there are standards for things like this–(format: “YYYY-MM-DD”), what is the earliest twenty-first century date where all of the digits are different?
Submit your answer to Gene Wirchenko <email@example.com>. Your answer should be in the form of a proof. That means to show how your answer must be correct. The deadline is Wednesday, April 16, 2014 at noon Pacific Time. I will post the answer shortly after.