# Search results

1. ### Boolean Matrix

Well if you have 1*1 on any column that value is autoamtically 1. So if you like at row 1 column one on each that is why I get a 1 in the corner
2. ### Boolean Matrix

Boolean values can only be 1 or 0. I think you are right that it is still wrong. I re did it and I got: [ 1 1 1 0 1 0 1 1 1]
3. ### Boolean Matrix

Homework Statement Homework Equations The Attempt at a Solution Does my logic seem right, I'm doubtin my anwsers.
4. ### Continuous Probability

Homework Statement f(x) = (3/4)(-x^2 + 6x - 8) for 2 < x < 4 (0 elsewhere) A) Find F(x) integral 2 to 4 ((3/4)(-x^2 + 6x - 8))dx B) Use F(x) to find P(3 < X < 3.5) integral 3 to 3.5 ((3/4)(-x^2 + 6x - 8))dx 11/32 C) Use F(x) to find P(X > 3.5) 1-( P(3 < X < 3.5)) = 21/31 D) Find E(X)...
5. ### Mean and STDev

Ok so here is what I have let me know if this looks better Mean: .21 87(0)+8(1)+3(2)+1(4)+1(3)=21/100 STDev: E[x^2]-[E[x]]^2 .45-(.21)^2=.4059 sqrt(.4059) STDEVA: .637
6. ### Mean and STDev

So would it be .45/100%= .0045, which seems also wrong but makes sense. Since the .45 is the number of quarters in the "system" sorta say, and then we accounted for 100% of the population.
7. ### Mean and STDev

So what is throwing me off is I think my calculation of the mean is incorrect. Because more people has 0 quarters then say 2 quarters, the the mean should theoretically be less then 2 correct?
8. ### Mean and STDev

So my answer of .64043 was correct?
9. ### Mean and STDev

I forgot to add in part of the problem statement. I've added that. x^2f(x)
10. ### Mean and STDev

Homework Statement Mind mean and STDev of number of quarters someone has on them at one time 0 - 87% 1 - 8% 2 - 3% 3- 1% 4 - 1% The first time I did this I assumed a population but she said that was wrong and not what she was looking for. Here was my new attempt: x^2f(x)= 0(.87) 1(.08) 4(.03)...
11. ### Probability of Opening a Pushbutton Lock

Alright I remember this! So : 1: 1/252 2: 1/252 * 251/252 3: 1/252 * 251/252 * 250/251 4: 1/252 * 251/252 * 250/251 * 249/250... Geometric: (1/252)/(1-(1/252)) = still get .003 tho :(
12. ### Probability of Opening a Pushbutton Lock

In your case you would be subtracting them, which would be arthemtic.
13. ### Probability of Opening a Pushbutton Lock

How can I set this up with the formula?
14. ### Probability of Opening a Pushbutton Lock

251/252 is not guessing the right number 250/251 would be not guessing the 2nd time (since we have one less guess made)
15. ### Probability of Opening a Pushbutton Lock

Could do a geometric series right. So: 1/252+1/251+1/250 +1/249.... 1/242 Just dont know hwo to set it up using that formula a(a-r^n)/1-r n=10 r=?
16. ### Probability of Opening a Pushbutton Lock

Would it just be 10/252 then? Then is part A right?
17. ### Probability of Opening a Pushbutton Lock

10 Digits chose 5 10!/(5!(10-5)!)= 252 I thought of it as 10*9*8*7*6=30240 5^10=9765625 ways to choose numbers ( this doesn't account for repeats not being allowed)
18. ### Probability of Opening a Pushbutton Lock

Homework Statement A password has numbers 0-9 in it. The password is 5 digits, repeats are not allowed, and order doesn't matter (I just have to have the correct 5 digit buttons depressed). A. If I guess at the password, what is the probability that the box will open? B. If I have completely...
19. ### Axioms of Probablity

Well technically with how the question is worded it the sample space is accounted for. I guess we we assume there is only 3 conditions of a cell phone it's not accounted for. If we assume they there could be another option that wasn't listed it does account for 100% of the cases.
20. ### Axioms of Probablity

Homework Statement Give an factory of cell phones there is a .5 rejections, .2 repaired, and .2 acceptable. Does this follow the axioms of probability. Homework Equations Sample space = 1; Probaby: 0 -1 P(AnB)=P(A)+P(B) The Attempt at a Solution Technically this does follow the axioms, there...
21. ### Probability of Situations

So I worded it wrong, there is only 3 friends and myself then. Just summarized the problem instead of writing it all out and wrote it wrong.
22. ### Probability of Situations

I do not think this would be a permutation because we could careless about the order right? We could have my friend would be app 3 and friend 2 be app 5. But they could hire app 2 5 3 9 etc. 12 nPr 4 = 11880 4! = 24 24/11880 = .002% This would be: 12!/(12-4)! = .002% which could be right...
23. ### Probability of Situations

Homework Statement Assume a job has 12 applicants, and 4 job openings. I want me and my 3 friends to all get the job. What is this probability. Homework Equations ! Factorial and Permuation & combinatoins The Attempt at a Solution Number of possible solutions: 12C4 = 495 Possible ways Number...

25. ### Laplace Transform

Homework Statement Homework Equations The Attempt at a Solution 1. I got Y(s) = (15s +18)/(5s^2+s-2) 2. I got Y(s) = (7s - 7iw + 1)/((s+4)(5 - iw)) Was just wanting to make sure I solved these right. I would type it out but without formating, it will look messy.