Same chapter3 marksDifficulty: Medium
In a class of 60 students, 35 play cricket, 28 play football and 12 play both. How many play neither?
Sets
3 marksDifficulty: Medium
State De Morgan's laws for sets.
Original Khojo Papers practice question — not from a past board paper.
Answer
The complement of a union is the intersection of the complements, (A ∪ B)′ = A′ ∩ B′; and the complement of an intersection is the union of the complements, (A ∩ B)′ = A′ ∪ B′.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
They are easily seen to be true from a Venn diagram.
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