Multiplication

Study Guide

TEST DATE: ______

Vocabulary:

Word / Definition / Example
Factor / The two numbers you are multiplying together / 7 x 8 = 56
Product / The answer to a multiplication problem / 7 x 8 = 56
Identity Property of Multiplication / Anything multiplied by 1 stays the same / 5 x 1 = 5
Zero Property of Multiplication / Anything multiplied by 0 is 0 / 3 x 0 = 0
Commutative Property of Multiplication / You can multiply two factors in any order and it will not change the product / 7 x 8 = 56
is the same as
8 x 7 = 56
Array / A model for multiplication illustrated by pictures or shapes in columns and rows / 3 x 4= 12

Special tricks for remembering facts:

Factor / Trick
8 / Remember the cow song from Have Fun Teaching on YouTube
9 / Finger trick: count on your fingers the factor other than 9 and put that finger down. Count the numbers on the left of your folded finger and the numbers on the right of your folded finger to find the answer.
10 / Ten is so nice! Add a zero behind the other factor

Strategies for solving multiplication problems:

  • Memorization
  • Skip Counting: skip count by one of your factors
  • Have Fun Teaching songs: find on YouTube…catchy tunes that will help make skip counting easier—especially the 8’s
  • Make a List: Skip count and keep track of your list of numbers to refer back to later
  • Break the Number Apart: When a factor is hard to multiply by, try breaking it up into two factors that are easier and then add them together:
  • 6 x 6

5 1

5 x 6 = 30

1 x 6 = 6

30 + 6 = 36

**REMEMBER: Everyone’s different. Until you get them memorized, find a strategy that works for you and stick with it!**

Be able to:

  • Solve multiplication problems with factors of 0-10
  • Solve two digit by one digit multiplication problems
  • Solve multiplication word problems
  • Recognize multiplication models such as arrays and number lines:

Five jumps of two; 5 x 2 = 10

Practice

Read the word problem. Underline, circle, or highlight the key word(s) and then solve.

1)The third grade teachers at Horizon decided to throw a party for their students. If each teacher has 24 students, how many students do they have to plan for?

2)Kyle was awesome at baseball and always hit homeruns. For his birthday, seven people gave him packages of baseballs. If there were eight balls in each package, how many baseballs did Kyle receive?

3)Miss Wasser came to visit Miss Strohl at her house and brought her dog, Jake. If Miss Strohl has three cats, how many paws were at her house during Miss Wasser’s visit?

4)**Challenge**

Adam bought three doughnuts for $0.75 each and two cups of coffee for $1.50 each. If he paid with a ten dollar bill, how much change would he get back?