Maths
DUNDALK INSTITUTE OF TECHNOLOGY | | | | | Bachelor of Science in Computing in Applications & Support - Semester 3 | Bachelor of Science in Computing in Networking & Support - Semester 3 | Bachelor of Science in Computing in Software Development - Semester 3 | | | Data Analysis for Computing | | Christmas 2010 | | | | | | | | | | | Dr. Fiona Lawless | | | | | | | Answer any FOUR questions | All questions carry equal marks | | | | DO NOT TURN THIS PAGE UNTIL INSTRUCTED | Question 1.
(a) The following 20 numbers relate to response times recorded when the new Carrolls network was being tested:
30.9 | 41.1 | 1.2 | 30.6 | 35.2 | 25.8 | 15.0 | 35.8 | 32.9 | 20.7 | 29.7 | 12.4 | 32.7 | 33.5 | 21.6 | 38.9 | 33.2 | 17.9 | 43.6 | 41.2 | Using a class width of 10, construct a grouped frequency distribution for this data set and then estimate the mean response time. Explain why your answer is only an estimate of the mean of this data set.
(5 marks)
(b) The numbers of SPAM EMAILS received by 750 DKIT computing students over a one week period, were recorded as follows:
No of SPAM EMAILS Received | Number of students | less than 5 | 68 | between 5 and 10 | 176 | between 10 and 15 | 244 | between 15 and 20 | 193 | between 20 and 25 | 42 | between 25 and 30 | 27 |
(i) Calculate the mean number of SPAM emails received by a computing student.
(4 marks)
(ii) Construct a histogram for the data. Use it to estimate the modal number of SPAM emails received.
(3 marks)
(iii) Construct an Ogive for the given data set. (3 marks)
(iv) Use your Ogive to estimate: the median number of SPAM emails received;
(a) The following 20 numbers relate to response times recorded when the new Carrolls network was being tested:
30.9 | 41.1 | 1.2 | 30.6 | 35.2 | 25.8 | 15.0 | 35.8 | 32.9 | 20.7 | 29.7 | 12.4 | 32.7 | 33.5 | 21.6 | 38.9 | 33.2 | 17.9 | 43.6 | 41.2 | Using a class width of 10, construct a grouped frequency distribution for this data set and then estimate the mean response time. Explain why your answer is only an estimate of the mean of this data set.
(5 marks)
(b) The numbers of SPAM EMAILS received by 750 DKIT computing students over a one week period, were recorded as follows:
No of SPAM EMAILS Received | Number of students | less than 5 | 68 | between 5 and 10 | 176 | between 10 and 15 | 244 | between 15 and 20 | 193 | between 20 and 25 | 42 | between 25 and 30 | 27 |
(i) Calculate the mean number of SPAM emails received by a computing student.
(4 marks)
(ii) Construct a histogram for the data. Use it to estimate the modal number of SPAM emails received.
(3 marks)
(iii) Construct an Ogive for the given data set. (3 marks)
(iv) Use your Ogive to estimate: the median number of SPAM emails received;