Question 4 Given \( B=\{5,6,7, \ldots, 20\} \), what is \( n(B) \) ? \( n(B)= \) Check Answer Question 5 Are the given sets equivalent? \( A=\{8,9,7,8,9,9\} \) and \( B=\{5,9,2,2,5,2\} \) yes no Check Answer

To find the number of elements in set \( B \), we need to count the number of elements in the set. Given set \( B = \{5,6,7, \ldots, 20\} \), we can see that the set contains the numbers from 5 to 20, inclusive. To find the number of elements in this set, we can subtract the first element from the last element and add 1. Therefore, the number of elements in set \( B \) is \( n(B) = 20 - 5 + 1 = 16 \). Now, let's move on to the second question. To determine if sets \( A \) and \( B \) are equivalent, we need to check if they have the same elements, regardless of the order or repetition of the elements. Set \( A = \{8,9,7,8,9,9\} \) and set \( B = \{5,9,2,2,5,2\} \). To check if sets \( A \) and \( B \) are equivalent, we can remove the duplicates from each set and compare the remaining elements. Set \( A \) without duplicates: \( \{8,9,7\} \) Set \( B \) without duplicates: \( \{5,9,2\} \) Since the sets \( A \) and \( B \) do not have the same elements, they are not equivalent.