Questions: Use the given information to fill in the number of elements for each region in the Venn diagram.
n(A ∪ B)=51, n(A ∩ B)=7, n(A)=34, and n(A′ ∪ B′)=73
The number of elements in region x is , the number of elements in region y is , the number of elements in region z is , and the number of elements in region w is
(Type whole numbers.)
Transcript text: Use the given information to fill in the number of elements for each region in the Venn diagram.
$n(A \cup B)=51, n(A \cap B)=7, n(A)=34$, and $n\left(A^{\prime} \cup B^{\prime}\right)=73$
The number of elements in region x is $\square$ , the number of elements in region y is $\square$ the number of elements in region $z$ is $\square$ and the number of elements in region w is $\square$
(Type whole numbers.)
Solution
Solution Steps
Step 1: Find the number of elements in region x.
We are given that $n(A) = 34$ and $n(A \cap B) = 7$. Region x represents the elements that are in A but not in B. So, $x = n(A) - n(A \cap B) = 34 - 7 = 27$.
Step 2: Find the number of elements in region y.
Region y represents the intersection of A and B, so $y = n(A \cap B) = 7$.
Step 3: Find the number of elements in region z.
We are given that $n(A \cup B) = 51$. Since $n(A \cup B) = n(A) + n(B) - n(A \cap B)$, we have $51 = 34 + n(B) - 7$. Therefore, $n(B) = 51 - 34 + 7 = 24$.
Region z represents the elements that are in B but not in A. So, $z = n(B) - n(A \cap B) = 24 - 7 = 17$.
Step 4: Find the number of elements in region w.
We are given $n(A' \cup B') = 73$. By De Morgan's law, $A' \cup B' = (A \cap B)'$. So, $n(A' \cup B') = n(U) - n(A \cap B)$.
Therefore, $73 = n(U) - 7$, which means $n(U) = 73 + 7 = 80$.
Region w represents the elements that are not in A or B.
$w = n(U) - n(A \cup B) = 80 - 51 = 29$.