Algebra

Rules for Growing Patterns

1

Continue the Addition Pattern

Find the rule and fill in the missing numbers.

3
6
9
15
?
5
10
20
25
?
4
8
12
20
?
2

Continue the Multiplication Pattern

Find the rule and fill in the missing numbers.

2
6
54
162
?
1
3
9
81
?
2
4
8
32
?
3

Subtraction Patterns

Fill in the missing numbers in each decreasing pattern.

100
90
80
60
?
50
45
35
30
?
200
175
150
100
?
4

Match the Pattern to the Rule

Draw a line to match each pattern to its rule.

2, 4, 8, 16, ...
1, 4, 7, 10, ...
5, 10, 15, 20, ...
3, 9, 27, 81, ...
Multiply by 3
Add 5
Multiply by 2
Add 3
5

Match More Patterns to Rules

Draw a line to match each pattern to its rule.

100, 90, 80, 70, ...
1, 2, 4, 8, ...
7, 14, 21, 28, ...
1000, 500, 250, 125, ...
Divide by 2
Add 7
Subtract 10
Double
6

What Is the Rule?

Circle the rule for each pattern.

4, 7, 10, 13, 16, ...

Add 2
Add 3
Add 4

2, 6, 18, 54, ...

Add 4
Multiply by 2
Multiply by 3

80, 70, 60, 50, ...

Subtract 5
Subtract 10
Divide by 2

1, 4, 16, 64, ...

Multiply by 4
Add 3
Multiply by 2
7

Write the Next Three Numbers

Identify the rule and write the next 3 numbers in each pattern.

6, 11, 16, 21, ___, ___, ___. Rule: ___

3, 6, 12, 24, ___, ___, ___. Rule: ___

500, 450, 400, 350, ___, ___, ___. Rule: ___

1, 5, 25, 125, ___, ___, ___. Rule: ___

8

Describe the Rule

Look at each pattern. Write the rule and find the next two numbers.

4, 8, 12, 16, 20, ___, ___ Rule: ___

1, 3, 9, 27, 81, ___, ___ Rule: ___

100, 90, 80, 70, 60, ___, ___ Rule: ___

2, 5, 8, 11, 14, ___, ___ Rule: ___

9

Describe More Rules

Write the rule and find the next two numbers.

7, 14, 28, 56, ___, ___ Rule: ___

1000, 800, 600, 400, ___, ___ Rule: ___

3, 5, 9, 15, 23, ___, ___ Rule: ___

10

What Comes Next?

Circle the next number in each pattern.

1, 2, 4, 8, 16, ?

20
24
32

50, 45, 40, 35, ?

25
30
20

3, 6, 12, 24, ?

36
48
30

7, 11, 15, 19, ?

22
23
25
11

More Next Numbers

Circle the next number in each pattern.

5, 8, 11, 14, ?

16
17
18

2, 10, 50, 250, ?

500
1000
1250

1000, 900, 800, 700, ?

500
600
650

1, 4, 9, 16, ?

20
24
25
12

Input-Output Tables

Complete each input-output table and write the rule.

Input: 1→4, 2→7, 3→10, 4→?, 5→? Rule: ___

Input: 1→3, 2→6, 3→12, 4→?, 5→? Rule: ___

Input: 2→5, 4→9, 6→13, 8→?, 10→? Rule: ___

13

Growing Shape Patterns

A pattern grows like this: Step 1 = 1 square, Step 2 = 3 squares, Step 3 = 5 squares. Answer the questions.

How many squares at Step 4? ___

How many squares at Step 5? ___

What is the rule? ___

How many squares at Step 10? ___

14

Another Growing Pattern

A pattern grows: Step 1 = 4 dots, Step 2 = 7 dots, Step 3 = 10 dots.

How many dots at Step 4? ___

How many dots at Step 6? ___

Write a rule to find the number of dots for any step: ___

How many dots at Step 20? ___

15

Create Your Own Growing Pattern

Design your own growing pattern.

My rule: ___ Step 1: ___ Step 2: ___ Step 3: ___ Step 4: ___ Step 5: ___

How many at Step 10? ___ How did you work it out? ___

16

Two-Step Rule Patterns

Some patterns use a two-step rule (e.g. multiply by 2 then add 1).

Pattern: 1, 3, 7, 15, 31, ___. Rule: ___

Pattern: 2, 5, 11, 23, 47, ___. Rule: ___

Pattern: 0, 1, 4, 13, 40, ___. Rule: ___

17

Home Activity: Pattern Creator

Create your own growing patterns!

  • 1Use blocks or counters to build a growing pattern. Draw each step.
  • 2Make a pattern that starts at 2 and doubles each time. How big does it get after 8 steps?
  • 3Create a decreasing pattern that starts at 1,000 and subtracts 75 each time.
  • 4Find a growing pattern in nature (e.g. petals on flowers, spirals in shells).
  • 5Challenge a family member with a pattern and see if they can find the rule.
18

Fibonacci-Like Sequences

In this sequence, each term = the two before it added together. Fill the missing numbers.

1
1
2
5
8
?
2
3
5
8
21
?
3
4
7
11
29
?
19

Arithmetic Sequences

An arithmetic sequence has a constant difference. Find the rule and complete each sequence.

8, 13, 18, 23, ___, ___. Common difference: ___

100, 85, 70, 55, ___, ___. Common difference: ___

-5, -1, 3, 7, ___, ___. Common difference: ___

20

Geometric Sequences

A geometric sequence multiplies by the same ratio each time. Complete each sequence.

3, 6, 12, 24, ___, ___. Common ratio: ___

500, 100, 20, 4, ___, ___. Common ratio: ___

2, 6, 18, 54, ___, ___. Common ratio: ___

21

Match Sequence Type to Rule

Draw a line to match each sequence to its rule type.

2, 5, 8, 11, ...
3, 6, 12, 24, ...
1, 1, 2, 3, 5, 8, ...
10, 7, 4, 1, ...
Subtract 3 (arithmetic)
Each term = sum of two previous
Add 3 (arithmetic)
Multiply by 2 (geometric)
22

Pattern Tables

Complete each pattern table.

Position: 1, 2, 3, 4, 5, 10. Term (×4 + 1): 5, ___, ___, ___, ___, ___

Position: 1, 2, 3, 4, 5, 10. Term (3n − 2): ___, ___, ___, ___, ___, ___

Position: 1, 2, 3, 4, 5. Term (n²): ___, ___, ___, ___, ___

23

Generalising Patterns with Algebra

Write an algebraic rule for the nth term of each pattern.

Pattern: 5, 10, 15, 20. nth term = ___

Pattern: 7, 9, 11, 13. nth term = ___

Pattern: 2, 5, 8, 11. nth term = ___

Pattern: 0, 3, 8, 15, 24. nth term = ___

24

Which Term Comes Next?

Circle the next term in each sequence.

Fibonacci: 13, 21, 34, ?

47
55
57

Arithmetic: -8, -3, 2, 7, ?

9
11
12

Geometric: 1,000, 500, 250, ?

100
125
150

Square: 1, 4, 9, 16, 25, ?

30
35
36
25

Sort Sequences by Type

Sort each sequence into the correct type.

2, 4, 8, 16
3, 6, 9, 12
1, 1, 2, 3, 5
10, 8, 6, 4
100, 10, 1, 0.1
1, 2, 4, 7, 11
Arithmetic
Geometric
Neither
26

Pattern Investigation: Square Numbers

Investigate the pattern of square numbers.

First differences of 1, 4, 9, 16, 25: ___

Second differences of those: ___

What do you notice about the second differences? ___

Predict the next square number using this pattern: ___

27

Counting Patterns in Shapes

Patterns of squares: Step 1 = 1 square, Step 2 = 5 squares, Step 3 = 13 squares. Each icon = 1 square.

Step 1
Step 2
Step 3
Step 4
1

What is the rule for this pattern?

2

How many squares at Step 5?

3

Write an algebraic rule for the nth term.

28

Patterns in Nature

Answer these questions about mathematical patterns in nature.

Sunflower seeds follow a Fibonacci spiral. The Fibonacci sequence starts 1, 1, 2, 3, 5, 8... List the next 5 terms: ___

The ratio of consecutive Fibonacci numbers approaches 1.618. This is called the ___

Find an example of a growing pattern in real life and describe the rule: ___

29

How Quickly Does It Grow?

Track how fast each sequence grows. Tally the size of terms 1-5.

ItemTallyTotal
Add 3 (e.g. 3,6,9,12,15)
Multiply by 2 (e.g. 1,2,4,8,16)
Square (1,4,9,16,25)
30

Creating Pattern Rules

Create a growing pattern that meets each condition.

Pattern that starts at 3 and grows by multiplying by 3: ___

Pattern where the 10th term is exactly 100: ___

Pattern where the differences are 2, 4, 6, 8 (triangle numbers): ___

31

Predicting with Patterns

Use the pattern rule to predict terms far in the sequence.

Rule: 2n + 3. What is the 20th term? ___. The 100th term? ___

Rule: 5n − 2. What is the 15th term? ___. The 50th term? ___

Arithmetic sequence: first term 4, common difference 7. What is the 12th term? ___

32

Comparing Two Growing Patterns

Compare these two patterns.

Pattern A: 2, 5, 8, 11 (add 3). Pattern B: 1, 3, 9, 27 (multiply by 3). Which is larger at term 5? ___. At term 10? ___

Which pattern grows faster in the long run? ___. Why? ___

33

nth Term Calculations

Calculate each term using the formula given.

Formula 3n + 1. Term 6 = ?

18
19
20

Formula 4n − 3. Term 5 = ?

17
20
21

Formula n². Term 8 = ?

16
64
81

Formula 2n². Term 4 = ?

16
32
64
34

Patterns with Ratios and Proportions

Investigate patterns involving ratios.

Ratio of 3:5 grows as 6:10, 9:15, 12:___, ___:25

A pattern where every term is 3/4 of the previous: Start at 256. List 5 terms: ___

If the ratio of boys:girls is 2:3 in every class, and there are 120 students total, how many girls? ___