Using the digits in 2011 (one 2, one 0, and two 1’s) and some basic arithmetic operations, generate the integers from 0 to 20. Usually, the operations that can be used in puzzles of this sort are the four basic ones: addition, subtraction, multiplication, and division. You may use these plus factorial and what I will call “triangular”.
n! is the product of the integers from 1 to n. e.g. 4! = 24. 0! is defined as 1. Without factorial, the 0 in 2011 would be nearly useless. It is a bad century for puzzles like this. “triangular” is is the sum of the integers from 1 to n. e.g. 4 triangular = 10.)
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, August 27, 2014 at noon Pacific Time. I will post the answer shortly after.
“So when will you have that report finished?”
“Pretty soon. I am 90% done.”
All too often, previously-unknown factors attack and now, it is going to take longer than expected. But it seems there is a rule that you can not go backwards on your percentages even if you now know that you are only, say, 40% done.
I was bit badly on this once on a uni programming course. I had one last test to do. I fully expected the test to pass, and if it did, I would be done with the coding and could write up the assignment. I was seconds away from being done, done, done!
Unfortunately, the test failed due to a peculiarity in the PHP programming language. It took me about two hours to get back to the point that I had thought I was at.
If you have something to do, there are three realistic possibilities: 1) you have not started it yet, 2) you have started it, or 3) it is done.
If you do need to track by number of things done, make sure that the things are fairly small. Spending two weeks on one thing makes for weird statistics.
Recently, I was walking downtown and saw a group of people blocking some of the sidewalk.
They were spread out over half the sidewalk. In fact, they were spread out over over half the sidewalk.
The issue: The odd duplication of “over” tickled my fancy.
The People’s Glorious Republic of Heinz has an unusual currency with only two denominations: five units and seven units. You have to pay someone using this currency. Work out how to do so for each of one to ten units. (Hint: The other person can give change.)
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, August 20, 2014 at noon Pacific Time. I will post the answer shortly after.