🦜🦚🦩The Intersection and Union of Sets🦜🦚🦩

 Welcome 👦👧boys and girls to another Mathematics class. Today, we will be learning about the intersection and union of sets.

What is a Set?

A set is just a collection of things (like numbers, toys, or names).
We usually list them inside curly brackets { }.

Example:
Set A = {1, 2, 3}

1. The UNION of Sets (∪)

Definition: The union of two sets is everything from both sets put together.
Think of it like: "Combine them all!"
Symbol: ∪ (like a cup that holds everything).

Rule: If an item is in Set A OR in Set B, it goes into the Union.

Example 1:
Set A = {1, 2, 3}
Set B = {3, 4, 5}
Union (A ∪ B) = {1, 2, 3, 4, 5}  

Example 2 (Real Life):
Set A = {Pizza, Burger, Fries} (Your favorite foods)
Set B = {Fries, Sushi, Cake} (Your friend's favorite foods)
Union (A ∪ B) = {Pizza, Burger, Fries, Sushi, Cake}
(This is all the food you both like together!)  

2. The INTERSECTION of Sets (∩)

Definition: The intersection of two sets is only the items that are in BOTH sets.
Think of it like: "What do they have in common?"
Symbol: ∩ (like an upside-down cup or a bridge connecting two things).

Rule: An item must be in Set A AND in Set B to go into the Intersection.

Example 1:
Set A = {1, 2, 3}
Set B = {3, 4, 5}
Intersection (A ∩ B) = {3}
(Because 3 is the only number that appears in both sets!) 

Example 2 (Real Life):
Set A = {Pizza, Burger, Fries} (Your favorite foods)
Set B = {Fries, Sushi, Cake} (Your friend's favorite foods)
Intersection (A ∩ B) = {Fries}
(Because Fries is the only food you BOTH like!)

Task 1: Complete the task in your book.
Set X = {Apple, Banana, Grape}
Set Y = {Grape, Orange, Melon}

1. What is the Union (X ∪ Y)?

2. What is the Intersection (X ∩ Y)?

Task 2:

Use the information from the Venn Diagram to find the intersection and union of the set.

2a. What is the intersection of set P and Q?

        Ans= PQ= {12, 6, 18}

2b. Find the union of set P and Q.

         Ans= P U Q = {2, 3 4, 6, 8, 9, 10, 12, 14, 15, 16, 18}

👦👧Boys and girls watch the video clips to get additional information on intersection and union of a set.

click and watch                                click and watch 

It's now activities time boys and girls.👇👇

Task 1:

1a. Write the union and the intersection of set M and N.

                M= {3, 6, 9, 12, 15}           N= {2, 4, 6, 8, 10, 12}

2b. Use the information in the Venn Diagram to find the intersection and union of set of R and S.

Task 2:

1.     Use the information given below to create a Venn Diagram.

W= {the whole numbers from 0 to 4}     X= {the counting numbers from 1-5}  

 

 

                     W ∪ X={                       }               W U X={                                               }

Task 3:

Liveworksheet Activities Time👇👇

1. Click and do the activity 

2. Click and do the activity 

3. Click and do the activity 

4. Click and do the activity 

5. Click and the activity 

Boys and girls hope you have fun learning about the intersection and union of a set.