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# Sets!! Time to have some fun!!

Set is a collection of well defined distinct objects. Like a various sorts things are stored in one single thing.

If two sets are A and B, set (A union B) represents a set where all the elements of set A and B are present. If A={1,2,3}, B={2,3,4,5,6,7} then (A U B )={1,2,3,4,5,6,7}

If two sets are A and B, set $\cap$ (A intersection B) represents a set where only the common elements of both A and B are present. If A ={1,2,3}, B= {2,3,4,5,6,7} then (A $\cap$ B ) = {2,3}.

n(A U B)=n(A)+n(B)-n(A $\cap$ B ) where n(set)= number of elements in a set, it is a very important formula to keep in mind.

• In a class of 50 students, 18 take math, 26 take economics, and 2 take both math and economics.  How many students in the class are not enrolled in either of them ?

1. 10
2. 8
3. 12
4. 6