1. A writer of the business traveller column of a newspaper believes that business travellers who flew on an Airbus's A380 aircraft before would

1. A writer of the business traveller column of a newspaper believes that business

travellers who flew on an Airbus’s A380 aircraft before would prefer flying on this

aircraft than on a Boeing’s B747 aircraft. To verify his claim, she asks a business

analyst to perform a survey for her. The business analyst interviews a random sample

of 100 business travellers who have flown on both A380 and B747. 64 business

travellers say that they prefer the A380 aircraft.

(i) Test, at the 1% level of significance, whether or not the writer’s claim is correct

using the rejection region approach. You must define the parameter clearly in your

answer.

(ii) Find the p-value of the hypothesis test in (i).

2. A business analyst of an international airline is in charge of reviewing the existing

aircraft boarding procedure and a newly introduced procedure. Over a two- week

period, 360 randomly selected passengers who used the existing boarding procedure

and 360 randomly selected passengers who used the new boarding procedures were

asked if they were satisfied with the boarding experience. The business analyst finds

that 216 passengers were satisfied with the existing boarding procedure and 270

passengers were satisfied with the new boarding procedure. The business analyst

claims that the new boarding procedure is better than the existing procedure.

(i) Test, at the 1% level of significance, whether or not the business analyst’s claim is

correct. You must define the parameters clearly in your answer.

(ii) Calculate the p-value for the above test.

(iii) If the senior management of the airline requires that the maximum error of the

estimation of the difference of the two population proportions to be 0.02 at the 95%

3. In an executive MBA unit, the managing director of a courier service learnt a

training program to improve employee’s work efficiency. She modified this training

program and then recruited 30 randomly selected employees to participate in the

training program. Before joining this training program, each employee’s work

efficiency was measured by a score sheet (min. 0 point, max. 100 points). Upon the

completion of the training program, employee’s work efficiency was measured again.

The managing director believed that her training program can improve employee’s

work efficiency by at least 10 points.

Do you think that the managing director’s claim is supported by the data? use

significance level 0.05 .

4. On average, a business statistics textbook has 1.5 typing mistakes (i.e. typos) per

10 printed pages. A new business statistics textbook of 750 pages has just been

published.

(i) Ten pages are randomly taken from this book. Find the probability that there are

more than two typos. Verify your answer using Excel.

(ii) Find the probability that less than 80 typos are found in this textbook. Verify you

answer using Excel.