Question

An individual's phone number contains seven digits, not including the area code, from the set A shown below.
A = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}

Set B represents the digits in Brent's phone number.
B = {5, 5, 5, 3, 0, 9, 9}

Set C represents the digits in Charlie's phone number.
C = {8, 6, 7, 5, 3, 0, 9}

How many even numbers are in the set ∼(B ∩ C)

Answer 1

First you need to find B ∩ C

Answer 2

B ∩ C is the set of everything that's in both sets B and C

So what numbers are in both sets B and C?

Answer 3

(0,3,5,9)?

Answer 4

now you turn to set A = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}

and you delete elements that are found in B ∩ C

So you start with {0, 1, 2, 3, 4, 5, 6, 7, 8, 9} and delete 0, 3, 5, 9 to get

{1, 2,4, 6, 7, 8}

Answer 5

So

∼(B ∩ C) = {1, 2, 4, 6, 7, 8}

Answer 6

the last step is to count the number of even numbers in the set {1, 2, 4, 6, 7, 8}

Answer 7

4

Answer 8

yep, there are 4 even numbers in ∼(B ∩ C) = {1, 2, 4, 6, 7, 8}

Answer 9

thank you!:)

Answer 10

you're welcome