Question 466 of 480
If X = {n²+1 : n is a positive integer and 1 ≤ n ≤ 5} and Y = {5n : same condition}, find X ∩ Y.
- {5, 10}
- {5, 10, 15}
- {2, 5, 10}
- {5, 10, 15, 20}
Correct Answer:
A
Explanation
X = {1²+1, 2²+1, 3²+1, 4²+1, 5²+1} = {2, 5, 10, 17, 26}. Y = {5*1, 5*2, 5*3, 5*4, 5*5} = {5, 10, 15, 20, 25}. Common elements: {5, 10}.