Just another hi :)

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Hi,

I'm learning statistics and probability on khan academy, It's been quite fun. I love math.

Ahoy-hoy.

Welcome to WP Althea.

Welcome to Wrong Planet!

Welcome to Wrong Planet. I had not heard of Khan Academy, so I looked it up.

Welcome to Wrong Planet!

Thank you all!

Howdy Howdy Howdy

Math is fun. It is hard work, but once you understand a new concept, it is very enjoyable.

By the way, here is a probability problem.

You have two jars containing red and blue balls. The first jar contains 4 red balls and 6 blue balls. The second jar contains 16 red balls and some number of blue balls. If you draw one ball from each jar, the odds that both balls are the same color is 44%. How many blue balls are in the second jar?

That was published in the Wall Street Journal a couple of years ago. They said that it came from one of the actuarial exams that actuaries take to become a fully credited actuary.

let P1 be the first bag, and P2 be the second:
P1(red)P2(red) + P1(blue)P2(blue) = 44/100
(4/10) * (16 / (16 + n)) + (6/10) * (n / (16 + n)) = 44/100
solving for n gives 4, hence four blue balls.

thaaanks for the problem! it was fun!!

Good job.

Most people can't seem to do that problem correctly. I haven't figured that out.

I have another problem, if you want it, that is interesting. Someone gave it to me years ago and I posted it at a place I used to work. Everyone immediately jumped in to do it on their computers. One problem is that the obvious way of doing the problem by recursion and is extremely inefficient. It could take days or weeks to run on the computers of thirty years ago.

Nobody realized that there was a related approach that they could use to solve it in a couple of seconds on the computer. Increase the numbers from the tens into the thousands and it shouldn't take more than a minute or two, but do it the obvious way and you may not be able to finish it before life on Earth is wiped out when the sun expands to the orbit of Venus.

That said, it can be solved without the computer, too.

Thanks!
It sounds interesting! I can fiddle with Python. I would like to try it

Okay. I'll have it in a minute or two.


... (time passing) ...

Aaron has bought a bag containing 100 pieces of candy consisting of 90 cherry candies and 10 lemon candies. He prefers the cherry candies but likes the lemon candies, too. Each day, Aaron randomly selects a piece of candy from the bag. If the piece of candy is cherry flavored, he happily eats the candy. But if the candy is lemon flavored, he puts the candy back in the bag, shakes it up, and randomly selects a piece of candy again. The second time, he eats the candy regardless of whether it is cherry flavored or lemon flavored.

What is the probability that the last piece of candy Aaron eats is lemon flavored?

Merry Christmas.

wow, sounds much harder. I'll tackle it in the morning, I won't use python.

Thank you again!

Zero
Unbeknownst to Aaron I got a bag of mixed lollies and have been dumping the aniseed ones in his bag and taking a lemon.

Welcome to WrongPlanet Altheasindy..hope you enjoy your visits. And if you celebrate Christmas,, a merry one to you .

I'm making progress. It's leading me into combinatorics, I'm slowly rebrushing on their concepts just by thinking about the problem. It's fun.