Two integers are selected from the first 1024 positive integral perfect squares. What is the probability that both of these numbers are fifth powers of integers?
Firstly, it would be polite to respond after each time someone answers a question. Especially when it is a 'real' answer.
** You already asked this question in its non-proofed form and I answered.
Secondly, if you copy the whole question into google you will get several readily available answers.
You did it again Melody. Called someone out for something not true, and provided a non-workable solution. All solutions on google require for you to pay.
This is a post I was referring to. It is rude to not respond and then just repost.
https://web2.0calc.com/questions/probability_37639#r1
Yes, the second part of my comment may not be correct. I appologise for that.
1024^2 = 1048576
1048576^(1/5) = 16
4/1024 * 3/1023 = 12/1047552 = 3/261888
EDIT: It is only my last disision that is incorrect 12 /1047552 = 1/87296 NOW our answers agree
Thanks Builderboi. Oh, and your answer is a lot more elegent than mine is
I got a different answer, Melody.
If a number is both a square and a 5th power, it must also be a perfect 10th power.
Note that \(1024^2 = 4^{10}\), so there are 4 numbers that work: \(1^{10}\), \(2^{10}\), \(3^{10}\), and \(4^{10}\)
There are \({4 \choose 2} = 6\) successes and \({1024 \choose 2} = 523776\) total outcomes.
So, the probability is \({6 \over 523776} = \color{brown}\boxed{1 \over 87296}\)