Find out the average and probability, Basic Statistics

Assignment Help:

Question 1:     

(a)  The time it takes to deliver a pizza after an order is placed is uniformly distributed between 20 and 50 minutes. What is the probability that a pizza will be delivered within half-an-hour after an order is placed?                                                                                                                                           

(b)  After completing a study, the Chicago O'Hare Airport managers have concluded that the time needed to get passengers loaded onto an airplane is normally distributed with a mean equal to 15 minutes and a standard deviation equal to 3.5 minutes.  Recently an Airbus A380 airplane required 22 minutes to get passengers on board and ready for take off. What is the probability that a flight will take 22 minutes or more to get passengers loaded?                                                                                                           

(c) The Haines Internet Services Company has determined that the number of customers who attempt to connect to the Internet per hour is Poisson distributed with a mean of 30 per hour.  The time between connect requests is exponentially distributed. Because of the system that Haines uses, if customer requests are too close together - 45 seconds or less - the connection will fail. Find the probability that a customer will fail to connect.

Question 2:                                                                                          

(a) The Commonwealth Bank Property Guide shows that the median value of houses in the New South Wales Hunter region in August 2008 was $261,000.  Suppose that the mean price was $276,000 and standard deviation of prices was $80,000. If you take a random sample of 100 houses, what is the probability that the sample mean will be less than $270,000? What assumptions did you have to make?    

(b) Skilled migrants accounted for 43% of all permanent arrivals to Australia in 2006-07. In comparison, Family Stream migrants accounted for 26% and Humanitarian Program migrants contributed 9%. Suppose a government department is conducting a follow-up study and randomly selects 60 migrants who arrived in the above period. What is the probability that more than 45% of the people in the sample are skilled migrants?                                                                                                                                                                                 

(c) Suppose that the population size is 500 and sample size is 50. Do you apply the finite population correction factor in calculating the standard error if the sampling is done with replacement?                               

Question 3:                                                                                                 

(a) The data below represent the lowest daily rate in NZ$ for a double room in a sample of motels and motor lodges in 20 New Zealand cities and towns in January 2008.                                         

City/Town

Room cost

 

City/Town

Room cost

Lake Taupo

130

 

Hamilton

140

Whitianga

110

 

Waitomo

80

Auckland

120

 

Whangarei

115

Paihia

90

 

Russell

115

Wellington

110

 

Kerikeri

85

Tauranga

79

 

Havelock North

115

New Plymouth

115

 

Thames

115

Hastings

115

 

Palmerston North

130

Napier

99

 

Wanganui

95

Gisborne

130

 

Rotorua

100

Construct a 95% confidence interval for the population mean lowest room rate.           

(b)  The Parental Leave Survey, carried out by University of Queensland researchers, collected information from 3,500 families with young children. It found that 26% of the mothers used some paid maternity leave, of which 18% used it at half-pay to double the duration. Construct a 95% confidence interval for the proportion of mothers taking paid maternity leave who wish to receive it at half-pay so as to lengthen the duration.  

(c)  Explain (including functions and arguments) what the following command in Microsoft Excel will find:

=AVERAGE(A2:A20) + TINV(0.05, ROWS(A2:A20-1))*STDEV(A2:A20)/SQRT(ROWS(A2:A20))       


Related Discussions:- Find out the average and probability

Discuss single control chart , Question 1 A courier company conducted ...

Question 1 A courier company conducted a brainstorming session amongst drivers to ascertain the reasons why it was unable to deliver items to households, always right first ti

State income tax, State income tax In most declares paycheck accounting...

State income tax In most declares paycheck accounting will involve a condition earnings tax. In those declares a company is necessary to hold the condition earnings tax that an

Women tend to work out together, You notice at the gym that it appears more...

You notice at the gym that it appears more women tend to work out together, while more men tend to work out alone.  To show whether this difference is significant, you collect data

Find the probability that the total weight of a full rack, Question: (a...

Question: (a) Packs of food have weights that are distributed with standard deviation 2.3 g. A random sample of 200 packets is taken. The mean weight of this sample is found t

Authorized travel period , Authorized travel period Then period when the ...

Authorized travel period Then period when the visitor is in authorized travel position away from the established stop and established property. Talk about OFFICIAL STATION, OFFIC

Comparing Two Samples, Ask qComparing Two Samples: 1. Apply the function "p...

Ask qComparing Two Samples: 1. Apply the function "plot" to the formula that relates the response "frequency" to the explanatory variable "march2007" in order to produce the two bo

Determine the correct interpretations - confidence interval, Which of the f...

Which of the following statements are correct interpretations of a 95% confidence interval for μ? (a) 95% of the observations in the sample will be contained in the confidence i

Description of sample at baseline, Description of Sample at Baseline 1...

Description of Sample at Baseline 1. Describe the sample characteristics and baseline values, comparing the two groups'characteristics. With any analysis, the first step

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd