Arrays
Arrange 12 dots into an array (there is more than one correct way).
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There are 3 rows of chairs. Each row has 5 chairs. Write the multiplication expression.
3 x 5
There are 7 rows. Each row has 3 crayons. How many crayons are there? Write a multiplication equation with a symbol for the unknown.
7 x 3 = ?
3 x 7 = ?
Bradley has 4 rows of hockey pucks with 5 hockey pucks in each row. How many hockey pucks does he have? Show how you got your answer.
20 hockey pucks
4 x 5 = 20
What is the answer called in a multiplication problem?
The product
There are 3 rows of flowers with 6 flowers in each row. Draw the array.
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8 x 2
There are 3 rows of students with 4 students in each row. How many students are there altogether? Write TWO multiplication equations with the answer in the equation.
3 x 4 = 12
4 x 3 = 12
Isabella put 6 books on each of her 5 bookshelves. How many books does she have? Show how you got your answer.
30 books
6 x 5 = 30
What are the numbers being multiplied together called in a multiplication problem?
The factors
There are 4 boxes with 3 books in each box. Draw the equal groups. Then draw an array.
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There are 4 rows of cars. Each row has 5 cars. Write TWO multiplication expressions to represent the situation.
4 x 5
5 x 4
There are 6 bags with 3 baseballs in each bag. Write a multiplication equation with a symbol for the unknown. Then write a multiplication equation that has the solution.
6 x 3 = ?
6 x 3 = 18
Anthony has 10 pages of baseball cards with 4 cards on each page. How many baseball cards does he have? Show how you got your answer.
40 cards
10 x 4 = 40
What is the difference between an expression and an equation?
An equation has an equal sign, an expression does not.
The number of cups on a shelf can be represented by the expression 2 x 6. Draw the array.
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Which of the following expressions could represent the number of students in our class?
a. 5 x 6
b. 8 x 4
c. 10 x 3
d. 5 x 7
b. 8 x 4
(This equals 32!)
There are 10 books in 2 boxes. How many books are in each box? Write a multiplication equation with a symbol for the unknown.
10 = 2 x ?
10 = ? x 2
Ella put 35 stuffed animals in equal rows of 5. How many rows of stuffed animals did she make? Show how you got your answer.
7 rows
5 x 7 = 35
What is the commutative property?
You can multiply two numbers together in any order and get the same answer.
E.g., 3 x 5 = 15 and 5 x 3 = 15