If A is the set of prime divisors of 18 and B = {2, 3}, which statement is correct?
Answer and explanation
Correct answer: A = B
The positive divisors of 18 are 1, 2, 3, 6, 9 and 18. Among them, the prime divisors are only 2 and 3, because both are prime and divide 18. The number 9 is a divisor but is not prime, so it cannot be included in A. Hence A = {2, 3} = B. The sets are equal, not in a proper-subset relationship, and A is certainly not empty.
Frequently asked questions
What is the correct answer to this question?
A = B
Why is this the correct answer?
The positive divisors of 18 are 1, 2, 3, 6, 9 and 18. Among them, the prime divisors are only 2 and 3, because both are prime and divide 18. The number 9 is a divisor but is not prime, so it cannot be included in A. Hence A = {2, 3} = B. The sets are equal, not in a proper-subset relationship, and A is certainly not empty.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: Equal sets and Subsets.
