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Question 4.20 (b)

Author	Message
HelloWorld Posts: 88	Posted 21:54 Jul 15, 2009 \| when it says average section size, what defines the size of a section? thanks
cysun Posts: 2935	Posted 22:25 Jul 15, 2009 \| HelloWorld wrote: when it says average section size, what defines the size of a section? thanks It's the number of students in the section.
HelloWorld Posts: 88	Posted 22:32 Jul 15, 2009 \| cysun wrote: HelloWorld wrote: when it says average section size, what defines the size of a section? thanks It's the number of students in the section. OK, so if my understanding is correct.. section with the same ID could be offered on the different year, and then take the average for the students that is registered on the section for every year? in this case though, no duplicates on year for same sections.. am i correct? thanks! Last edited by HelloWorld at 22:44 Jul 15, 2009.
cysun Posts: 2935	Posted 22:45 Jul 15, 2009 \| HelloWorld wrote: cysun wrote: HelloWorld wrote: when it says average section size, what defines the size of a section? thanks It's the number of students in the section. OK, so if my understanding is correct.. section with the same ID could be offered on the different year, and then take the average for the students that is registered on the section for every year? I think the wording "per year taught" is confusing and somewhat misleading. A couse may be taught in different years, but a section is only taught in one particular year. I think the question means "The aveage section size by year". For example, if there are 2 sections in 2001, and one had 20 students and the other had 15 students, then the average section size for 2001 is 17.5.
HelloWorld Posts: 88	Posted 22:48 Jul 15, 2009 \| very clear! thanks a lot! :)
Urvashi Posts: 34	Posted 10:44 Jul 17, 2009 \| HelloWorld wrote: very clear! thanks a lot! :) Is it mandatory to use the avg aggregate function ? it is mentioned in the question , but i think avg is based on the number of rows in the resulting table(which will be number of years) but here average needs to be calculated on the basis of number of sections in a year ... can avg function do that ? thank you
cysun Posts: 2935	Posted 08:36 Jul 18, 2009 \| Urvashi wrote: HelloWorld wrote: very clear! thanks a lot! :) Is it mandatory to use the avg aggregate function ? it is mentioned in the question , but i think avg is based on the number of rows in the resulting table(which will be number of years) but here average needs to be calculated on the basis of number of sections in a year ... can avg function do that ? thank you You can use the avg function or calculate average by doing something like sum(...)/count(...). Either way is fine.