If C = {x : x is a positive divisor of 12 and x is odd}, what is the roster form of C?
Answer and explanation
Correct answer: C = {1, 3}
The roster form lists every element that satisfies both conditions. The positive divisors of 12 are 1, 2, 3, 4, 6, and 12. Among these, only 1 and 3 are odd; 2, 4, 6, and 12 are even and must be excluded. Therefore, C = {1, 3}, so option A is correct. Option B lists all positive divisors without applying the oddness condition, while option D includes 5, which is not a divisor of 12.
Frequently asked questions
What is the correct answer to this question?
C = {1, 3}
Why is this the correct answer?
The roster form lists every element that satisfies both conditions. The positive divisors of 12 are 1, 2, 3, 4, 6, and 12. Among these, only 1 and 3 are odd; 2, 4, 6, and 12 are even and must be excluded. Therefore, C = {1, 3}, so option A is correct. Option B lists all positive divisors without applying the oddness condition, while option D includes 5, which is not a divisor of 12.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: Sets and their representations.
