How many terms do I need to know

We have to be able to write a few paragraphs on certain topics for an upcoming exam. We have a list of 20 topics. 8 will be given, and from there we will choose 4 to write about.
What's the minimum number of topics I need to get down really well?

(It's a more complicated version of having 3 topics, 2 being on the exam, and writing about 1 - so you'd have to prepare for two minimum).

If you really want to cover your bases you'll need to know 16. you can only afford to not know four because out of the ones you get there will only be four that you don't have to answer. If you study for less than 16 of them there will be a chance that you get more than four you aren't prepared for.

total topics = 20

to be asked = 8

to be answered = 4

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if you must answer all 4, you need to learn 16 topics

if you answer 3 o/o 4, then, 15.

if you must answer 2 o/o 4, then 14

if only 1 o/o 4, then 13.

if none o/o 4, the number of topics to be learn becomes 0.


[if you want practical advice, then go for 2/3 of all results[i.e. 16/1`5/14/13] . chances are that you will do most & if worse come to worst, at least half. [its a practical & not mathematical advice]

all of them

You need to know at least 18 topics or the 90 % of your topics..
So that you have higher possibility that you can answer appropriately well.
But remember, you still should have a good foundation with the other topics.
As in at least you can say something about a topic that you have no doubt that it is true.

On the 20 topics :
First : Choose 5 topics that interests you most.
Second : Choose 10 topics that you think is easy for you.
Third : Choose 5 topics that you think is hard for you.

Now, you need to have a background to the topics that are really hard for you.