b PX77 When X77 07PX77 Pz07 1 07580 0242 cP60X75 When X60 z 60 7010 1

B px77 when x77 07px77 pz07 1 07580 0242 cp60x75 when

This preview shows page 1 - 2 out of 2 pages.

b. P(X≥77) = ? When X=77, z = 77 70 10 = 0.7 P(X≥77) = P(z≥0.7) = 1-0.7580 = 0.242 c. P(60≤X≤75) = ? When X=60, z = 60 70 10 =− 1 When X=75, z = 75 70 10 = 0.5 P(60≤X≤75) = P(-1≤z≤0.5) = P(z≤0.5) - P(z≤-1) = 0.6915 – 0.1587 = 0.5328 d. Probability of 0.95 on the lower tail corresponds to z =1.645 1.645 = x 70 10 x = 1.645 × 10 + 70
Image of page 1
x = 86.45 3.) Phone calls arrive at the rate of 48 per hour at the reservation desk for Regional Airways. a. Compute the probability of receiving three calls in a 5-minute interval of time. b. Compute the probability of receiving exactly 10 calls in 15 minutes. c. Compute the probability of receiving at most 3 calls in 5 minutes. 3.) a. µ = 48/12 = 4, x = 3 f (3) = 4 3 e 4 3 ! = 0.195 b . µ = 48/4 = 12, x = 10 f (3) = 12 10 e 12 10 ! = 0.105 c. µ = 48/12 = 4, x = 3, 2, 1, 0 f (at most 3) = f(0) + f(1) + f(2) + f(3) = 4 0 e 4 0 ! + 4 1 e 4 1 ! + 4 2 e 4 2 ! + 4 3 e 4 3 ! = 0.018 + 0.073 + 0.147 + 0.195 = 0.434 Standard Deviation STAT – Edit – enter numbers – STAT CALC – 1-vars stats Binomial Probabilities (Binomial pdf) P(x=C) = binom pdf (n,p,c) n = # of trials 2 nd VARS – binom pdf – enter data p = prob. Of success x-value Probability Distribution (random variables) 2 nd VARS Normal pdf (probability density function) -used to find a single value of the random variable x. Normal cdf (cumulative distribution function) -used to find the cumulative probability from zero up to the same input value of random variable x. InvNorm -used to find the x-value given the probability region is to the left of the x-value. A sample statistic is a piece of statistical information you get from a handful of items. A discrete variable is a variable which can only take a countable number of values. In this example, the number of heads can only take 4 values (0, 1, 2, 3) and so the variable is discrete . The variable is said to be random if the sum of the probabilities is one. The combination rule is a special application of the partition rule
Image of page 2

You've reached the end of your free preview.

Want to read both pages?

  • Summer '18
  • David Grimmett
  • Normal Distribution, Probability theory, Cumulative distribution function

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern

Stuck? We have tutors online 24/7 who can help you get unstuck.
A+ icon
Ask Expert Tutors You can ask You can ask You can ask (will expire )
Answers in as fast as 15 minutes
A+ icon
Ask Expert Tutors