Lesson 3.2: Multiplication Facts

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Transcript Lesson 3.2: Multiplication Facts

Multiplication
Facts
Homework Review
Mental Math
On your white board, try skip counting by…
20s
20, 40, ______, _______, _______
50s
50, ______, _______, _______, _______
8s
8, _______, _______, ________, _______
Back by 7s, 0, -7, ________, ________, _______
Math Message
Take out your multiplication/division fact
triangles.
Tell a friend how you think these fact triangles
will be used.
Multiplication/Division facts Table
Identify the following:
•Symbols for multiplication
and division
•Products
•Factors and factor pairs
•multiples
•Square numbers
•Turn around facts
Definitions
• Products – the answer in a multiplication problem
• Factors – 2 or more numbers that multiply together to
give you a product
Example: 6,2 are factors of 12 so are 3,4
• factor pairs – just the 2 factors that multiply together
• Multiples – the products in a specific number’s time table
– Example – Multiples of 5 are: 5, 10, 15, 20…
• Square numbers – the product of a number multiplied by
itself
– Example – 3*3=9
• Turn around facts – a pair of multiplication facts where
the numbers are reversed, but the answer stays the
same –
– Example – 2*7=14, 7*2=14
Multiplication Shortcuts
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0 times any number is 0
1 times any number equals that number
2 times any number is double that number
10 times any number, write the number
then write a 0 after the number
Other ways to solve multiplication
problems
Partner Activity
Practice your facts. Give your facts to a partner and they’ll
test you.
Sort your facts into an “I got it” pile and a “Practice again” pile.
Study your “Practice again” pile on your own for a few
minutes, then give them to your partner to test you again.
Math Boxes page 57
Wrap it up
• Give an example of a turn around fact
• Name 2 square numbers
• What’s the rule multiplying by 10?
• What are factors?
Tonight’s Homework