math puzzles

- Thirty-six entangled officers of Euler: Quantum solution to a classically impossible problem - - Original Paper: - -

It's no wonder people don't trust statistics. It seems far too many are statistically innumerate. Measuring Risk Literacy: The Berlin Numeracy Test http://journal.sjdm.org/11/11808/jdm11808.pdf The Berlin Numeracy Test was found to be the strongest predictor of comprehension of everyday risks...

So... in South Africa yesterday, the Powerball results were interesting, and when they are this interesting, a lot of people begin to question whether there are some shenanigans going on. The powerball here is structured as follows: Select 5 balls from a pool of 45 Select 1 powerball from a...

This book was officially released in the U.S. on Tuesday, Jan 21, 2020; though it had been released in a couple of other countries some time before then. The main body of the book is about 311 pages long (or maybe 314, depending on how you count). However, the Index begins on page...

Long story short Lotto power ball built over several weeks to 38 mill They said the chances of winning were 36 mill to one Two people got it. Are the chances of a person getting the right numbers 36m-1 at the same time as another person gets them 36m-1, higher than 36m-1, or still just...

So I've been going back and forth with a friend of a friend online regarding the Monte Hall Problem. It has devolved into disagreements about probabilities and I'm having a hard time. He has gone into 'actual' and 'perceived' odds. My latest example is 'When you dive by my house, I'm either...

This is a list of values I had generated, while preparing some... "mathematically interesting"... material for my upcoming birthday party. (I was born on March 10, 1977.) The first person to figure out what it is gets a "prize" of some sort. 101010 1120 222 132 110 60 52 46 42 39 36 33 30 2C...

Math disabled person here asking for assistance. If an observer is on the ground and the moon is full and at its apex in the sky and an aircraft moving at 400 kph passes in front of on the observers line of sight to the Moon. How do you calculate how long it will be visible while passing said...

So, lots of math debate in some hockey circles arising from how the NHL's draft lottery was conducted. (feel free to skim this part the real question is later) The lottery works like this: there are 14 balls, 4 of which are drawn to give a 4 number combination. There are 1001 possible...

I'm too lazy to figure this out myself, but it goes like this. When I'm logging into an on-line poker game -Texas Holdem- , they throw little ' factoids ' onto the screen while it's loading. One I see a lot is " The chance of being dealt pocket Aces is 220 to 1.. " Correct number or not...

A vacant lot has opened up next door to my work place that was turned into a temporary car park. When they first opened they were charging $18 per day and the place was empty for weeks. No one wanted to use it. Eventually they dropped the price to $7 per day and within a couple of weeks the car...

For anyone unaware of the rules: You have 2 tries to get 100 total. If you get 100 on the first spin you stop. The wheel has slots in increments of 5 from 5 to 100. (So 20 slots.) (I don't think it matters but here is the sequence: 5¢, $1.00, 15¢, 80¢, 35¢, 60¢, 20¢, 40¢, 75¢, 55¢, 95¢...

Was surfing and came across this problem: When I was 4 years old, my sister was half my age. Now my sister is 12 years old. How old am I? Then I got to noticing that there was a huge thread of wrong and/or incomplete answers! 1,755 answers and not a single one as far as I could find got it...

Who want to be a millionaire had their Whiz Kids series and the asked a math question. So the kid had to figure this out entirely using his brain. They gave the number 123456787700000 (actually they listed the last digits but I forgot what they were) and asked what was the square root. There...

This is based on a problem I tutored a college student on today, which baffled us both. We have four variables, just call them A,B,C and D that when multiplied together give us our total costs. Our original budget called for A=42,000, B=.07, C=.90 and D=$4,750, meaning a total cost (A*B*C*D)...

Hi all, I have a math question. I am grading exams for my upper division history class and a student came to me concerned because they thought the two students in front of them were cheating. The first student would tap on something on their test. Student 2 would nod and write something down...

Okay, this is probably going to seem blindingly obvious once somebody points out how to do it, but for some reason I can't seem to figure it out. If you have an equation such as YX = Z, how do you solve for X? For example, with 2x = 3, X has to be 1.5849625, but I can't figure out the proper...

Guys, I'd love some help with this math problem that's been bouncing around in my head for a while. I've posted something similar to this before, and I never really got an answer that I could understand and made sense. It's something that's been bothering me for years, and it's so...

Not knowing the answer to this has bugged me for ages... If an event is hypothesized to have probability x, how many observations of the event not happening does it require to invalidate the hypothesis, or of being confident that 'x' is wrong? e.g. I hypothesize that there is a 1 in 100 of an...

This is probably trivial for anyone who really know how to calculate probabilities. If you have a wheel like the one on "Wheel of Fortune" that has 12 segments, and only one of them is yellow, then the probability of hitting yellow with one spin of the wheel is one in twelve. What is the...

I was reading a story today (sorry no link handy but google is your friend) about Warren Buffett/Quicken Loans offer of 1 billion $ to anyone who submits a perfect NCAA bracket for this year's tourney. The story insisted the odds were one in a billion. That seems ridiculous to me, but I'm not...

....to anyone who can fill out a perfect March Madness bracket. But before you get your hopes up, there's a quintillion possible permutations. http://www.cnbc.com/id/101351399 Steve S

So my fifth grade son had this problem on his Math Team placement test: 31. An equilateral triangle has a perimeter of 15 inches. What is its area? a. 25 sq. in. b. 7.5 sq. in. c. 15 sq. in. d. 12.5 sq. in. He missed the problem and his homework was to have a parent explain the problems to...

I didn't want to derail the other current Lotto thread so have started this thread to ask . . . What is the better bet? One attempt at winning with 3,838,380 to one odds for the attempt, or ten attempts at winning with 38,383,800 to one odds for each attempt? Or are they both the same?

OK, so we've all seen the websites that say getting this number + that number = good or bad. This question is a bit different, and I was wondering if it would be a statistical curiosity. It is at least for me. Keep in mind this actually happened here at work. Funny stuff: User A buys 2...

For years, I've been telling people that it's as likely for you to get the above numbers as something like 35,32,18,16, 28, 21. People can't seem to believe it. Is this actually the case, or am I making a fool of myself?

here I am again struggling with math. I have to solve this system. 6x -y +3z =16 x+ 3y -z= -2 3x + 3y -4z = -1 I took the second and third equations and eliminated the x to get my final answer to be -6y -7z =5 Then, I took the first and third equations and eliminated the x to get my...

Not really. But I read in this article that NASA are perfectly happy to let 550kg of satellite fall randomly to the earth. They calculate odds of hitting someone at 3200 to 1. This seems a little too probable to me. For some reason it reminded me of the perils of celebratory gunfire. What...

Hi folks, my girl friend and I recently bought a hammock for my rooftop terrace. It didn't come with extra rope, so my girl friend went to a home improvement store later that day and bought some. I told her not to be too thrifty and buy something strong, as the forces pulling at the ropes of a...

I've just taken the Bang goes the Theory Big Risk Test. All answers were multiple choice. One of the questions was as follows: I picked the answer nearest to the one I calculated from those available (95%, 83%, 17% and 5%, IIRC): The value I calculated was... Have I missed something or...