- Per Receipt In The Last Year Was 380 Test Whether There Is An Increase In The Mean Amount In This Year At 5 Level Of 1 (201.47 KiB) Viewed 18 times
- Per Receipt In The Last Year Was 380 Test Whether There Is An Increase In The Mean Amount In This Year At 5 Level Of 2 (252.97 KiB) Viewed 18 times
per receipt in the last year was $380. Test whether there is an increase in the mean amount in this year at 5% level of significance. State your assumption(s) and/or approximation(s). (7 marks) Answer 2. (a) An organizing committee of four people has a chairman and three committee members. If a committee is formed by choosing four people from a group of twenty-five people at random, calculate the total number of committees that can be formed. (4 marks Answer Video (b) A survey is conducted by Students' Office recently to collect the preference of final year students to enroll development programme in the next semester. The results show that 90% of the students would enroll an intellectual development programme, 84% of them would enroll a social development programme and 2% of them would neither enroll any one of these two kinds of programme. (1) What is the probability that a randomly selected final year student would enroll both intellectual development and social development programmes? (4 marl Answer (3 mar (ii) What is the probability that a randomly selected final year student would enroll only one of these two programmes? Answer (iii) Given that a randomly selected final year student would enroll an intellectual development programme, calculate the probabilit a that this student would not enroll a social development programme. (4 mar Answer (c) There are three factories, namely Factories A, B and C, producing a specific type of canned food. The percentage shares of th canned food among Factories A, B and C are 45%, 35% and 20%, respectively. From historical records, the percentages of cann food produced by Factories A, B, and C having weight below the specification limit are 3%, 5% and 7%, respectively. A randomly selected canned food has weight below the specification limit, calculate the probability that this canned food is produced by Fac (5 ma
1. In order to study the length of time after billing for customers to settle the payments, a manager of a virtual bank took a random sample of 100 credit card invoices. A frequency table for the data on payment time, ie, the number of days between the invoice date and the payment receipt date, was constructed as below. Payment time (in days) Number of invoices 0 9 7 10 19 20 20 29 18 30 39 19 10 59 6 (a) Calculate the mean, mode, standard deviation and interquartile range. (8 marks (b) Calculate the coefficient of skewness using results in (a) and interpret your result briefly. 2 marks] (c) In order to encourage carly payment, the following scheme is introduced: • For payments made before the mean payment time, the company refunds the customers for each invoice $50 a day for the number of days before the mcan payment time. • For payments made after the mean payment time, the company charges the customers for each invoice $100 a day for the number of days after the mean payment time. llow me on average will the bank receive spend per invoice on the above 100 invoices under this scheme? 16 marke) (a) Develop a 1% confidence interval for the man payrrent time of all credit card INVOICE. murky