How many total subsets does the one-element set A = {9} have?
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Answer and explanation
Correct answer: 2
If a set has n elements, its total number of subsets is 2ⁿ, because each element can either be included in a subset or excluded from it. Here A = {9} has n = 1 element, so the number of subsets is 2¹ = 2. These two subsets are the empty set ∅ and the set {9} itself. Therefore option B is correct.
Frequently asked questions
What is the correct answer to this question?
2
Why is this the correct answer?
If a set has n elements, its total number of subsets is 2ⁿ, because each element can either be included in a subset or excluded from it. Here A = {9} has n = 1 element, so the number of subsets is 2¹ = 2. These two subsets are the empty set ∅ and the set {9} itself. Therefore option B is correct.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: Sets and their representations.
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