1. P

    need help in stats question pls!!

    A manager of an apartment store reports that the time of a customer on the second floor must wait for the elevator has a uniform distribution ranging from to 1 to 4 minutes. If it takes the elevator 15 seconds to go from floor to floor, find the probability that a hurried customer can reach the...
  2. A


    A company makes parts for a machine. The lengths of the parts must be within certain limits or they will be rejected. A large number of parts were measured and the mean and standard deviation were calculated as 3.1 m and 0.005 m respectively. Assuming this data is normally distributed and 99.7%...
  3. A

    statistics for engineers question please help

    I need to write an original question. I will use your answer as a guide to write an original question by myself. I couldn't find a guide or some examples from books or videos. I would reallly appreciate if you know and let me know where I can also find some examples . I dont know where or how...
  4. C

    Math Help: How to Calculate Weights for Multiplicative Model with Dummy Variables

    Hi Everyone, My question is how do I calculate weights for Y=W1X1*W2X2*WNXN where N is the number of independent variables. I could use logarithms to convert this to an additive model, but each of the independent variables are binary/dummy variables. Here is some background. Assume...
  5. S

    Intro Stats Problem.

    A student takes a true or false test with 15 questions. He guesses on every question. 1) Find the probability that he gets atleast 1 question right 2) Find the probability he gets 60% or higher. I am stuck. I know it is something with perms and coms. Any help would be great.
  6. G

    Probability Help

    Hello! Taking an introductory course on statistics in college. Confused about one question. It reads: The IRS reports that 15% of the tax returns where the adjusted gross income exceeded $1 million will be subject to computer audit. For a particular year, a CPA completed 16 returns where the...
  7. J

    Simple Probability Question

    OK, so I am wondering about something and am not good with probability, but maybe someone here has the answer You have a die with only 4 sides, with the numbers 1-4 written on the sides. You roll the die 5 times. What is the probability of the number 2 showing up: Once? Twice? Three times...
  8. J

    Help with regression analysis and 95% confidence interval

    Hello! We have a couple of tasks for an assignment where we need to use regression analysis and 95% confidence interval, we're not sure on how to do it so figured I'd ask you guys for help. We don't really need the result of the actual task, but rather an detailed explanation to how to do...
  9. B

    Help with gathering statistic information.

    Here is what I have done thus far. I can identify what each of the required information is, but I don't think I'm getting it exact. Here is my problem: A heavy equipment manufacturer introduces new models of their backhoes and forklifts, and sells several of these machines. A few months...
  10. K

    Probability- Combinations

    I need help getting started with this question. We've done combination questions, but not with percents, and its throwing me off. Computer Products Corporation (CPC) produces microchips. The microchips are inspected at the end of the production process at a quality control station. Out of...
  11. C


    How would I solve this problem? If I roll a fair die 4 times. X is the number of times 1 or 2 are observed in 4 rolls. What is the minimum number that X takes? What is the maximum number that X takes? What is the probability of observing 3 successes in 4 rolls? What is the probability of...
  12. J

    Chi square help

    The student population of local college is approximately one-third blond and two-thirds other hair color. Over a 2-day period, the hair color of each student entering the student union building is tallied,with the following results: blonds, 452; others 1,548. Determine whether blonds and others...