My Math Forum  

Go Back   My Math Forum > College Math Forum > Advanced Statistics

Advanced Statistics Advanced Probability and Statistics Math Forum

LinkBack Thread Tools Display Modes
September 27th, 2013, 02:59 PM   #1
Joined: May 2013

Posts: 6
Thanks: 0

Binomial distribution

So, this is what I have to calculate. If average 30% of 2100 visitors are buying ice cream and if an ice cream costs $100 calculate probability to earn at least $60 000 (more or equal to 60 000).

My assumption: we have binomial distribution with parameters B(2100, 0.3), n=2100, p = 0.3 and q = 1-p = 0.7.
If I put those values in formula for described distribution its too much complicated to calculate it. I was thinking about approximation with normal distribution and this is what I got so far:
n*p = 630
sqrt(n*p*q) = 21
P = 1-P(X<=600) = 1- phi(2827), and I'm stuck here.
I'll be happy to see your ideas.

Thank you
Burn is offline  
September 28th, 2013, 01:16 PM   #2
Global Moderator
Joined: May 2007

Posts: 6,762
Thanks: 697

Re: Binomial distribution

600 is (10/7)x(standard deviation) < mean. Look up table of standard normal distribution to get the probability for < -10/7.
mathman is offline  

  My Math Forum > College Math Forum > Advanced Statistics

binomial, distribution

Thread Tools
Display Modes

Similar Threads
Thread Thread Starter Forum Replies Last Post
Binomial distribution r-soy Probability and Statistics 2 November 16th, 2013 04:05 AM
Binomial distribution luke93 Advanced Statistics 3 March 20th, 2013 12:35 PM
the mean of a binomial distribution biosavart Probability and Statistics 4 December 10th, 2010 10:17 PM
Binomial Distribution wulfgarpro Probability and Statistics 2 June 8th, 2010 01:21 AM
Poisson distribution and binomial distribution questions latkan Advanced Statistics 1 May 11th, 2009 05:49 AM

Copyright © 2019 My Math Forum. All rights reserved.