Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
Multiplication as Repeated Addition: Multiplication is the process of adding the same number again and again. For example, if you have 4 groups of 3 flowers (), it can be written as . Visually, this looks like 4 separate plates with 3 flowers on each plate.
The Multiplication Sign: The symbol is used to represent 'times' or multiplication. In the expression , the symbol tells us to take 5 groups of 2. It can be read as '5 times 2 is 10'.
Equal Groups: Multiplication is only used when groups are equal in size. If you have 3 bags and each bag contains exactly 5 marbles, you have 3 equal groups. If the bags had different numbers of marbles, you could not use simple multiplication.
Skip Counting on a Number Line: Multiplication can be visualized as jumps on a number line. To find , you start at 0 and take 3 jumps of 4 units each (). The spot where you land is the product.
Order Property (Commutative Property): Changing the order of the numbers does not change the answer. and . Visually, an array of dots with 2 rows and 5 columns contains the same total number of dots as an array with 5 rows and 2 columns.
Multiplying by Zero: Any number multiplied by is always . For example, . This is like having 8 boxes with nothing inside them; the total number of items is zero.
Multiplying by One: Any number multiplied by stays the same. For example, . This is like having 1 group of 6 items, which is just 6 items.
Multiplication Tables and Patterns: Tables from 1 to 10 follow specific patterns. For example, the table of 5 always ends in or (), and the table of 10 always ends in ().
📐Formulae
💡Examples
Problem 1:
There are 6 bundles of sticks. Each bundle has 10 sticks. How many sticks are there in total?
Solution:
Number of bundles = . Sticks in each bundle = . Total sticks = .
Explanation:
Since there are 6 equal groups of 10, we multiply the number of groups by the quantity in each group to find the total.
Problem 2:
A car has 4 wheels. How many wheels do 7 cars have? Use repeated addition and multiplication.
Solution:
Repeated Addition: . Multiplication Fact: . Total wheels = .
Explanation:
We add the number 4 (wheels) seven times (for 7 cars), which is the same as calculating 7 times 4.