Recent content by wolfmanzak

Homework Statement People in a given community who have a certain disease is 0.005. A test is available to diagnose the disease. If a person has the disease, the probability that the test will produce a positive signal is 0.98. If a person does not have the disease, the probability that the...

I just have a question of "why/how?" I know that for instance \mathbf v=\omega \hat k \times \mathbf r where \mathbf v is my vector for velocity, \omega is my angular velocity and \mathbf r is my position vector from a point on the axis of rotation of a wheel to a point on the outer edge of the...

Homework Statement In a random pattern of eight bits used to test a micro-circuit, each bit is equally likely to be 0 or 1. Assume the values of the bits are independent. a. What is the probability that all eight bits are 1? b. What is the probability that exactly three of the bits are...

Homework Statement The proportion of people in a given community who have a certain disease is 0.005. A test is available to diagnose the disease. If a person has the disease, the probability that the test will produce a positive signal is 0.98. If a person does not have the disease, the...

I'm with you now I think. But is it true that: P(A^c|B)=1-P(A|B) as well as P(A|B^c)=1-P(A|B)? My book only has the first equation and I wanted to verify that the second was true as well. It works just as you said but I just wanted to make sure that I knew exactly why and that I'm not making up...

I'm with you now I think. But is it true that: P(A^c|B)=1-P(A|B) as well as P(A|B^c)=1-P(A|B)? My book only has the first equation and I wanted to verify that the second was true as well. It works just as you said but I just wanted to make sure that I knew exactly why and that I'm not...

Homework Statement A certain delivery service offers both express and standard delivery. Eighty-five percent of parcels are sent by standard delivery and 15% are sent by express. Of those sent standard, 80% arrive the next day, and of those sent express, 95% arrive the next day. A record of...

I think I understand the concept now. It makes a little more sense after these explanations. Thank you both.

Homework Statement Two identical stones are dropped from a tall building, one after the other. Assume air resistance is negligible. While both stones are falling, what will happen to the vertical distance between them? Homework Equations a) It will increase. b) It will first...

Unfortunately that is the exact way the problem is written which is why I'm also a bit confused. I'm inclined to agree with you on the belief that order doesn't matter, but I wasn't entirely sure. I've tried finding a good example or a source of info on the internet but have yet to find one...

Homework Statement Let A be the set of all strings of a's and b's of length 4. Define a relation R on A as follows. For all s,t \in A, sRt, s has the same first two characters as t. s=baaa t=abaa Homework Equations The Attempt at a Solution I just want to know if the order of the first two...

So if I pick z \in E_{a} this would mean that because a~z and that b~a(by symmetry of equivalence classes)we would have b~a and a~z and thus b~z(transitivity) and thus z is in the equivalence class of b. Would this be enough to show that the two equivalence classes of a and b respectively were...

Thanks, I can't believe I didn't see that. I've got it figured out now. I appreciate all of the help.

Not sure I follow you. Are you saying that \frac{1}{k*(k+1)} = \frac{1}{k} - \frac{1}{k+1}? How would that help? Sorry, I just don't follow you at the moment.

I have tried adding (k+1), 2(k+1), (k+1)^{2}...all of these to both sides of the equation and still cannot make it work. What do I need to add to the equation so that I can prove P(k+1)? Would I add something like \frac{1}{(k+1)((k+1)+1)}? I'm running out of ideas. I really need an answer to...