If A = {x ∈ Z : −4 ≤ x < 3}, how many elements are in A?
Advertisement
Answer and explanation
Correct answer: 7
Because x is an integer, the values in the interval are −4, −3, −2, −1, 0, 1, and 2. The lower boundary −4 is included because the symbol is ≤, whereas 3 is excluded because the symbol is <. Counting the listed integers gives 7 elements. Thus A is a finite set with cardinality 7, and option B is correct.
Frequently asked questions
What is the correct answer to this question?
7
Why is this the correct answer?
Because x is an integer, the values in the interval are −4, −3, −2, −1, 0, 1, and 2. The lower boundary −4 is included because the symbol is ≤, whereas 3 is excluded because the symbol is <. Counting the listed integers gives 7 elements. Thus A is a finite set with cardinality 7, and option B is correct.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: The Empty Set, Finite and Infinite Sets, Equal Sets.
Advertisement