Multiplication and Rectangles

Multiplication and Rectangles

We are continuing to work with multiplication.

Students will be arranging square tiles into rectangles to find factors of 6, 12, and 18.

They can turn the rectangles around and find that changing the order of the factors in a multiplication sentence does not change the product (3 X 6= 18 and 6 X 3= 18). This is called a turn-around fact.

They will also continue filling in their multiplication table.

Using Rectangles in Multiplication

The rectangle above has a side of 5 and a side of 3.

The multiplication problem would be 5 X 3 or 3 X5.

They count the number of tiles on each side to make their multiplication problem. (3 tiles on the left hand coulmn and 5 tiles on the bottom row)

They would then total the number of tiles to get the product of that multiplication problem.

Practice: Keep practicing multiplication flash cards, add 4, 6, and 7.

Links: Websites about rectangle multiplication

http://nlvm.usu.edu/en/NAV/frames_asid_192_g_2_t_1.html

www.eduweb.vic.gov.au/edulibrary/public/teachlearn/student/mathscontinuum/partialproducts1.ppt

Handy Facts

Multiplication

We are beginning our unit on Multiplication. Students have already been introduced to multiplication using pictures and words. Students will now take their prior knowledge and begin studying multiplication facts. We will be working with 0, 1, 2, 3, 5, and 10. These were chosen because these multiplication facts are easy to remember and are familiar to students.

Students will use a multiplication table to record and retrieve multiplication facts.

The students will be able to identify and use patterns for multiplication facts 0, 1, 2, 3, 5, and 10.

Key Vocabulary

Factor

Multiple

Product

The Language of Multiplication. 3 X 5= 15. We say fifteen is the product of three and five. We say fifteen is a multiple of 3 because it is the product of 3 and another whole number 5. Five and three are called factors of 15.

Patterns for Remembering the Facts

Patterns for 0: All multiples of 0 are 0

Patterns for 1: Any number times 1 is itself

Patterns for 2: All multiples of 2 are even

All multiples of 2 are doubles

All multiples of 2 end in 0, 2, 4, 6, or 8

Patterns for 5: All multiples of 5 end in 0 or 5.

When even numbers are multiplied by 5, the product ends in 0.

When odd numbers are multiplied by 5, the product ends in 5.

Patterns for 10: All multiplies of 10 end in 0

When ten is multiplied by any number, the product is the same

number with an extra 0 on the end.

Practice:

Use the flashcards to help your child with their multiplication facts. Work on 0, 1, 2, 3, 5, and 10's.

Links:

Multiplication Websites with Multiplication Tables

http://www.mathsisfun.com/tables.html

http://www.aplusmath.com/cgi-bin/Homework_Helper/mtable

http://math2.org/math/general/multiplytable.htm