If A = {a, b, c, d}, how many subsets with exactly 2 elements are in P(A)?
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Answer and explanation
Correct answer: 6
To form a subset with exactly two elements from a four-element set, choose 2 elements at a time without regard to order. The number is given by the combination formula C(4, 2) = 4!/(2!2!) = 6. These six pairs are all members of P(A), because every subset of A belongs to its power set.
Frequently asked questions
What is the correct answer to this question?
6
Why is this the correct answer?
To form a subset with exactly two elements from a four-element set, choose 2 elements at a time without regard to order. The number is given by the combination formula C(4, 2) = 4!/(2!2!) = 6. These six pairs are all members of P(A), because every subset of A belongs to its power set.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: Power Set and Subsets.
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