Recent content by k77i

yes it was the standard deviation of the means and I don't get why it would be wrong, I used excel to calculate it.. Anyways the correct interval was (8.5,31.5)

Homework Statement To test the efficacy of a new cholesterol-lowering medication, 10 people are selected at random. Each has their LDL levels measured (shown below as Before), then take the medicine for 10 weeks, and then has their LDL levels measured again (After). Before After...

Yes it is the standard deviation. I copied the question word for word.. In any case it's too late, the homework set is closed and apparently the accepted answer was 0307419079428789. I think I was supposed to use excel to find the exact value to the correct amount of significant figures..

im not sure what u mean by which region but my hart goes to a point z?

Homework Statement The top-selling Red and Voss tire is rated 60000 miles, which means nothing. In fact, the distance the tires can run until wear-out is a normally distributed random variable with a mean of 75000 miles and a standard deviation of 5000 miles. A. What is the probability...

I put all the numbers (0.0307).. The chart I have for the z-score only goes upto 4 decimal places so I'm not sure how much it's actually supposed to go up to

Thank you both for the help with part B. As for part A, since its a webwork assignment, it tells me when I enter an incorrect answer. I guess it's possible that there might be some sort of problem with the webwork.

Homework Statement Suppose that X is normally distributed with mean 95 and standard deviation 17. A. What is the probability that is greater than 126.79? B. What value of X does only the top 16% exceed? Homework Equations z= (X-(mean of x))/standard deviation The...

Thanks a lot for all the help. There really is a problem with that question, so my teacher will be probably be excluding it if he can't fix the bug.

Well this is a webwork assignment so if I enter the correct answer it let's me know. Is 1/3 not supposed to be the correct answer?

But my answer to a) worked out: p(A U B)/p(B) = [(1/3)(3/5)]/(3/5) = 1/3 was this just a coincidence because the 'correct' formula would give me the same answer?

Homework Statement A box contains one yellow, two red, and three green balls. Two balls are randomly chosen without replacement. Define the following events: A: \{ One of the balls is yellow \} B: \{ At least one ball is red \} C: \{ Both balls are green \} D: \{ Both balls are of the...

Ok then suppose that before i look for the velocity, i want to find the kinetic energy first. If i use the equations E= (gamma)m(0)c^2 and E(0) = m(0)c^2 , i can find the value for gamma, which gives me 3.2. if i then use the equation (gamma -1)m(0)c^2 to find the kinetic erergy it gives me...

but how would i calculate the gamma value if i don't have the velocity?

Homework Statement A proton (rest mass 1.67x10^-27 kg) has total energy that is 3.2 times its rest energy. What is: a) the kinetic energy of the proton (in joules) b) the magnitude of the momentum of the proton (in kg*m/s) c) the speed of the proton (in terms of the speed of light...