Multiplying by 12

Multiplying by 12

What will you learn today?

Today you will…

Learn a strategy for multiplying numbers when you don't know the answer right away.

Multiple Choice

What is this?

• Milk carton

• An egg carton

• Chicken holder

• Chicken container

Multiple Choice

How many eggs will fill this carton?

• 12

• 11

• 10

• 13

Multiple Choice

What word can we use for a group of 12 things?

• dime

• dollar

• 12 things

• dozen

A dozen means that there are 12 things.

​- I can count each row to find the number of eggs in a carton.

Dozen!!!

• dozen = 12

• 6 + 6 = 12

​

​How many eggs will fill each row?

Other ways to count 12's

Here is another way to count the eggs.

• I can count them by 2s.

  • 2, 4, 6, 8, 10, 12.

​Replace with sub-header

Other ways to count 12's (continued)

I can also split the carton so that 10 is in one group.

• So I have 10 plus 2.

• 10 + 2 = 12

How many eggs will fill two cartons?

​

​Let's try stacking 2 egg cartons!

2 Egg Cartons

To find how many eggs would fill two cartons, we can add the group of 12 in one carton and the group of 12 in the other carton.

Draw

What addition equation can I write to show how many eggs there are?

Draw

What multiplication equation can I write to show how many eggs there are? *

12 + 12 = 24

12 x 12 = 24

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Two Egg Cartons 2 Types of Equations

Ways to show 24 eggs

Here's another way to show that 24 eggs will fill two egg cartons.

• 10 is an easy number to multiply , so I will split each egg carton into 2 groups, with 10 on one side and 2 on the other.

Ways to show 24 eggs(continued)*

There are 2 groups of 10 eggs on the left side of the carton.

• What is 2 times 10? _______

There are 2 groups of 2 eggs on the right side of the carton.

• What is 2 times 2? _______

• What is 20 plus 4? _______

We are going to take a stack of 6 egg cartons.

​

Let's kick it up a notch!

Draw

What multiplication problem can we solvento figure out how many eggs will fill six egg cartons?*

Draw

Use the splitting strategy to figure out how many eggs will fill five egg cartons.

We will complete page 2 today.

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Go to your workspace book!