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Number - Multiplication and division facts for 2, 3, 4, 5, 8, and 10

Grade 3IGCSE

Review the key concepts, formulae, and examples before starting your quiz.

🔑Concepts

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Multiplication as Repeated Addition: Adding the same number multiple times (e.g., 3 x 4 is 4 + 4 + 4).

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Division as Equal Sharing or Grouping: Splitting a total into equal parts.

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The Commutative Property: The order of numbers in multiplication does not change the result (e.g., 2 x 5 = 5 x 2).

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Inverse Relationship: Multiplication and division are opposites. If 3 x 8 = 24, then 24 ÷ 3 = 8.

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Doubling Strategy: To find the 4 times table, double the 2 times table. To find the 8 times table, double the 4 times table.

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Patterns in Tables: The 5 times table always ends in 0 or 5; the 10 times table always ends in 0; the 2, 4, and 8 tables always result in even numbers.

📐Formulae

Multiplication: a×b=ca \times b = c

Division: c÷a=bc \div a = b

Commutative Property: a×b=b×aa \times b = b \times a

Fact Families: If a×b=ca \times b = c, then c÷b=ac \div b = a and c÷a=bc \div a = b

💡Examples

Problem 1:

Calculate 4×84 \times 8.

Solution:

32

Explanation:

Using the doubling strategy: 2×8=162 \times 8 = 16. Doubling 16 gives 16+16=3216 + 16 = 32. Alternatively, count by 4s eight times: 4, 8, 12, 16, 20, 24, 28, 32.

Problem 2:

Find the missing number: 40÷□=440 \div \square = 4.

Solution:

10

Explanation:

Use the inverse relationship. Ask yourself, '4 times what equals 40?' Since 4×10=404 \times 10 = 40, the missing number is 10.

Problem 3:

A baker puts 3 cookies in each bag. If he has 27 cookies, how many bags can he fill?

Solution:

9 bags

Explanation:

This is a division problem: 27÷327 \div 3. Recall the 3 times table: 3×9=273 \times 9 = 27. Therefore, 27 cookies shared into groups of 3 results in 9 bags.

Problem 4:

Which is greater: 5×45 \times 4 or 3×83 \times 8?

Solution:

3×83 \times 8 is greater.

Explanation:

First, calculate 5×4=205 \times 4 = 20. Next, calculate 3×8=243 \times 8 = 24. Since 24 is greater than 20, 3×83 \times 8 is the larger value.