Basic Math

Number patterns | Fifth Grade

Number Patterns - Fifth Grade

Complete Notes & Formulas

What is a Number Pattern?

A number pattern (or sequence) is an ordered list of numbers that follow a specific rule. The rule tells us how to get from one number to the next.

Parts of a Pattern

Terms: The numbers in a pattern

Rule: The instruction for finding the next term

First term: The starting number

Types of Number Patterns

TypeDescriptionExample
IncreasingNumbers get larger2, 5, 8, 11, 14...
DecreasingNumbers get smaller50, 45, 40, 35, 30...
RepeatingA set of numbers repeats1, 2, 3, 1, 2, 3...
MultiplicationMultiply by same number3, 6, 12, 24, 48...

1. Use a Rule to Complete a Number Pattern

What is a Pattern Rule?

A pattern rule is an instruction that tells you how to find the next number in a sequence.

Common Pattern Rules

Addition Rule: Add the same number each time

Example: Add 5 → 3, 8, 13, 18, 23...

Subtraction Rule: Subtract the same number each time

Example: Subtract 7 → 100, 93, 86, 79, 72...

Multiplication Rule: Multiply by the same number each time

Example: Multiply by 2 → 5, 10, 20, 40, 80...

Division Rule: Divide by the same number each time

Example: Divide by 3 → 81, 27, 9, 3, 1...

Combined Rules: More than one operation

Example: Add 3, then subtract 1 → 10, 13, 12, 15, 14...

Steps to Complete a Pattern

Step 1: Look at the given numbers

Step 2: Find the difference or relationship between consecutive terms

Step 3: Identify the rule (add, subtract, multiply, divide)

Step 4: Apply the rule to find missing numbers

Step 5: Check your answer by applying the rule again

Examples

Example 1: Complete the pattern: 7, 12, 17, 22, __, __

Step 1: Find the difference

12 - 7 = 5, 17 - 12 = 5, 22 - 17 = 5

Step 2: Rule: Add 5

Step 3: Apply the rule

22 + 5 = 27, 27 + 5 = 32

Answer: 27, 32

Example 2: Complete: 80, 72, 64, __, __, 40

Difference: 72 - 80 = -8 (subtract 8)

Rule: Subtract 8

64 - 8 = 56, 56 - 8 = 48

Answer: 56, 48

Example 3: Rule: Start at 5, add 1, then add 2, then add 3, and so on

5 + 1 = 6

6 + 2 = 8

8 + 3 = 11

11 + 4 = 15

15 + 5 = 20

Pattern: 5, 6, 8, 11, 15, 20...

2. Compare Patterns

What Does It Mean to Compare Patterns?

Comparing patterns means looking at two or more patterns and finding how they are similar or different.

Ways to Compare Patterns

1. Compare Rules: Are the rules the same or different?

2. Compare Terms: Which pattern has larger/smaller numbers?

3. Compare Growth Rate: Which pattern increases/decreases faster?

4. Compare Relationships: Is one pattern related to the other?

Steps to Compare Patterns

Step 1: Write both patterns

Step 2: Find the rule for each pattern

Step 3: Compare corresponding terms (1st to 1st, 2nd to 2nd, etc.)

Step 4: Look for relationships or patterns between the two sequences

Examples

Example 1: Compare these patterns

Pattern A: 3, 6, 9, 12, 15... (Rule: Add 3)

Pattern B: 5, 10, 15, 20, 25... (Rule: Add 5)

Comparison:

• Both are increasing patterns

• Pattern B grows faster than Pattern A

• Pattern B terms are always larger

• Both patterns share the number 15

Example 2: Compare related patterns

Pattern A: 2, 4, 6, 8, 10... (Rule: Add 2)

Pattern B: 4, 8, 12, 16, 20... (Rule: Add 4)

Relationship:

Pattern B = Pattern A × 2

Every term in B is double the corresponding term in A

Example 3: Using a table to compare

PositionPattern A (×3)Pattern B (×5)Difference
1352
26104
39156

The difference between patterns increases by 2 each time!

3. Complete an Increasing Number Pattern

What is an Increasing Pattern?

An increasing pattern (also called a growing pattern) is a sequence where each term is greater than the previous term.

Types of Increasing Patterns

1. Constant Addition Pattern

Add the same number each time

Example: 10, 15, 20, 25, 30... (Add 5)

2. Increasing Addition Pattern

The amount you add increases each time

Example: 2, 3, 5, 8, 12... (Add 1, add 2, add 3, add 4)

3. Multiplication Pattern

Multiply by the same number each time

Example: 2, 6, 18, 54... (Multiply by 3)

How to Find the Rule

Find the difference between consecutive terms

Examples

Example 1: Complete: 13, 18, 23, 28, __, __, __

Find differences:

18 - 13 = 5

23 - 18 = 5

28 - 23 = 5

Rule: Add 5

28 + 5 = 33, 33 + 5 = 38, 38 + 5 = 43

Answer: 33, 38, 43

Example 2: Complete: 1, 3, 6, 10, 15, __, __

Find differences:

3 - 1 = 2

6 - 3 = 3

10 - 6 = 4

15 - 10 = 5

Rule: Add 2, then 3, then 4, then 5... (increases by 1 each time)

15 + 6 = 21, 21 + 7 = 28

Answer: 21, 28

4. Complete a Multiplication Number Pattern

What is a Multiplication Pattern?

A multiplication pattern is a sequence where each term is found by multiplying the previous term by the same number.

Formula

Next Term = Previous Term × Common Ratio

How to Find the Multiplier

Divide any term by the previous term

Multiplier = Second Term ÷ First Term

Common Multiplication Patterns

MultiplierPattern Example
×2 (Double)3, 6, 12, 24, 48, 96...
×3 (Triple)2, 6, 18, 54, 162...
×41, 4, 16, 64, 256...
×52, 10, 50, 250, 1250...

Examples

Example 1: Complete: 4, 12, 36, __, __

Find multiplier:

12 ÷ 4 = 3

36 ÷ 12 = 3

Rule: Multiply by 3

36 × 3 = 108, 108 × 3 = 324

Answer: 108, 324

Example 2: Complete: 5, 10, 20, 40, __, __

Multiplier: 10 ÷ 5 = 2

Rule: Multiply by 2 (doubling pattern)

40 × 2 = 80, 80 × 2 = 160

Answer: 80, 160

Example 3: Find the 6th term: 3, 15, 75, 375, ...

Multiplier: 15 ÷ 3 = 5

5th term: 375 × 5 = 1,875

6th term: 1,875 × 5 = 9,375

Answer: 9,375

5. Number Patterns: Word Problems

Real-Life Applications

Number patterns appear in many real-world situations like:

Saving money regularly

Growing plants or populations

Building structures with blocks

Seating arrangements at events

Distance traveled at constant speed

Steps to Solve Word Problems

Step 1: Read the problem carefully

Step 2: Identify the pattern in the situation

Step 3: Write the first few terms as numbers

Step 4: Find the rule

Step 5: Apply the rule to answer the question

Examples

Problem 1: "Maya saves $5 in week 1, $10 in week 2, $15 in week 3. If this pattern continues, how much will she save in week 6?"

Identify pattern: 5, 10, 15...

Rule: Add $5 each week

Continue:

Week 4: $20

Week 5: $25

Week 6: $30

Answer: Maya will save $30 in week 6

Problem 2: "A bacteria colony doubles every hour. If there are 8 bacteria at 1:00 PM, how many will there be at 4:00 PM?"

Identify pattern: Doubling (×2)

1:00 PM: 8 bacteria

2:00 PM: 8 × 2 = 16

3:00 PM: 16 × 2 = 32

4:00 PM: 32 × 2 = 64

Answer: 64 bacteria at 4:00 PM

Problem 3: "A theater has 20 seats in row 1, 25 seats in row 2, 30 seats in row 3. If this pattern continues, how many seats are in row 8?"

Pattern: 20, 25, 30...

Rule: Add 5 seats per row

Row 4: 35, Row 5: 40, Row 6: 45, Row 7: 50, Row 8: 55

Answer: Row 8 has 55 seats

6. Number Patterns: Mixed Review

Practice All Pattern Types

Mixed review includes all types of patterns: addition, subtraction, multiplication, division, and complex patterns.

Problem-Solving Strategy

1. Look: Examine the given terms

2. Think: Ask yourself questions:

• Are numbers getting larger or smaller?

• Is there a constant difference?

• Is multiplication or division involved?

• Is the pattern more complex?

3. Test: Check if your rule works for all terms

4. Apply: Use the rule to complete the pattern

Mixed Practice Examples

Problem 1: 100, 90, 80, 70, __, __

Type: Decreasing pattern

Rule: Subtract 10

Answer: 60, 50

Problem 2: 2, 6, 18, 54, __, __

Type: Multiplication pattern

Rule: Multiply by 3

Answer: 162, 486

Problem 3: 1, 4, 9, 16, 25, __, __

Type: Square numbers (1², 2², 3², 4², 5²...)

Next terms: 6² = 36, 7² = 49

Answer: 36, 49

Problem 4: 10, 12, 15, 19, 24, __, __

Type: Variable addition (complex pattern)

Differences: +2, +3, +4, +5...

24 + 6 = 30, 30 + 7 = 37

Answer: 30, 37

Problem 5: 5, 10, 8, 16, 14, 28, 26, __, __

Type: Alternating pattern

Rule: Double, then subtract 2

26 × 2 = 52, 52 - 2 = 50

Answer: 52, 50

Quick Reference: Pattern Rules

OperationHow to Find RuleExample
AdditionSubtract consecutive terms4, 9, 14, 19 → Add 5
SubtractionSubtract consecutive terms50, 42, 34, 26 → Subtract 8
MultiplicationDivide consecutive terms3, 12, 48, 192 → Multiply by 4
DivisionDivide consecutive terms1000, 100, 10, 1 → Divide by 10

💡 Important Tips to Remember

Always check your rule by testing it on all given terms

Look for patterns in the differences between consecutive terms

Increasing patterns: Terms get larger (add or multiply)

Decreasing patterns: Terms get smaller (subtract or divide)

✓ Some patterns may have more than one rule (alternating patterns)

Multiplication patterns grow much faster than addition patterns

✓ Write down your work step-by-step to avoid mistakes

✓ In word problems, identify the numbers before finding the pattern

✓ Practice makes perfect - the more patterns you solve, the easier they become!

🧠 Memory Tricks for Finding Pattern Rules

For Addition/Subtraction Patterns:

Ask: "What do I add or subtract to get from one number to the next?"

For Multiplication/Division Patterns:

Ask: "What do I multiply or divide by to get from one number to the next?"

The "STOP" Method:

See the pattern

Test your rule

Operate to find next terms

Prove it works!

If stuck, try this:

1. Check if it's skip counting (2, 4, 6... or 5, 10, 15...)

2. Check if it's doubling (×2) or tripling (×3)

3. Check if there's an alternating pattern (two rules taking turns)

Master Number Patterns! 🔢🎯

Patterns are everywhere - in math, nature, music, and art!

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