SSAT Middle Level: Quantitative • Patterns and Sequences

Use pattern reasoning to predict a later term.

Spot the hidden rule in a list of numbers or shapes to find what comes next.

SSAT Middle Level illustration with a test notebook, quantitative function, and reading book
Inside this lesson 10 sections 5 questions 6 figures

SECTION 1

Historical Context & Motivation

People have spotted patterns in numbers for thousands of years. Ancient builders in Egypt used patterns to stack stones perfectly. Later, math whizzes like Fibonacci found cool rules in nature, like flower petals. These ideas help us predict what happens next in a list.

3000 BC • Egyptian Pyramids

Workers used repeating patterns to build strong shapes.

1202 • Fibonacci Sequence

Italian mathematician spots numbers in pinecones and rabbits.

1800s • Arithmetic Sequences

Math teachers teach kids to add the same number each time.

Today • SSAT Tests

You use patterns to solve quick math puzzles!

Patterns solve the puzzle of 'what's next?' You will see lists on the SSAT. Spot the rule to pick the right answer fast. You can do this!

SECTION 2

Core Principles of Pattern Reasoning

A pattern is a rule that repeats. Look for what changes the same way each time. Common types include adding a fixed number or multiplying by one.

1

Arithmetic Pattern

Add or subtract the same number each step. Like 2, 5, 8, 11 (add 3).
2

Geometric Pattern

Multiply by the same number. Like 3, 6, 12, 24 (×2).
3

Square Numbers

Each term is a number squared. Like 1, 4, 9, 16 (1², 2², 3², 4²).
4

Shape Patterns

Count shapes that grow. Like triangles: 1, 3, 6, 10.
✦

Key Takeaway

Patterns are like levels in your favorite video game. Each level adds the same challenge. Spot the rule, and you level up to the next term!

SECTION 3

Visualizing Patterns

Visualizing Patterns: Arithmetic Sequence Each term increases by the same amount — a constant difference of +3 2 Term 1 5 Term 2 8 Term 3 11 Term 4 14 Term 5 +3 +3 +3 +3 Pattern Rule Each term is found by adding 3 to the previous term. To predict Term 5: 11 + 3 = 14 General Formula aₙ = 2 + 3(n−1) Known terms Predicted term
Arrows show adding 3 each time. The next term is 14.

See the steady jumps? This visual arrow path makes patterns easy to spot. Follow the rule to the end.

SECTION 4

Mathematical Framework

Math gives formulas for patterns. An arithmetic sequence adds a fixed number, called d. Start with a₁ (first term). The nth term is a simple rule.

ARITHMETIC SEQUENCE FORMULA

an=a1+(n−1)×daₙ = a₁ + (n − 1) × d

aₙ = nth term, n = position, d = common difference (like +3)

GEOMETRIC SEQUENCE FORMULA

an=a1×r(n−1)aₙ = a₁ × r⁽ⁿ⁻¹⁾

r = common ratio (like ×2)

Plug in numbers step by step. You got this on the SSAT!

SECTION 5

Detailed Pattern Breakdown

Triangular Number Pattern Each term adds a new row at the bottom Term 1 1 dot Term 2 3 dots Term 3 6 dots Term 4 10 dots Term 5 — Predict! 15 dots +2 +3 +4 +5 🔍 Pattern Rule Each new term adds one more row at the bottom. The new row has as many dots as the term number. Formula: Term n = n × (n + 1) ÷ 2 Sequence: 1 , 3 , 6 , 10 , 15 , … = newly added row = predicted row (Term 5)
Triangles build up: stage 1 (1), stage 2 (3), stage 3 (6), stage 4 (10), stage 5 (15).

Count the extras added each time. This shape growth matches adding 1, then 2, then 3. Predict by seeing the build-up.

SECTION 6

Worked Example

Find the next term: 4, 7, 10, 13, ?

Step-by-Step Solution

  1. 1

    Step 1: Check differences

    7 − 4 = 3, 10 − 7 = 3, 13 − 10 = 3. Add 3 each time.
    Common difference d = 3
  2. 2

    Step 2: Use formula for 5th term

    a₅ = 4 + (5 − 1) × 3 = 4 + 12 = 16
    16
  3. 3

    Step 3: Verify

    13 + 3 = 16. Matches!
    Pattern confirmed

SECTION 7

Strengths & Comparisons

Pattern TypeRuleExample
ArithmeticAdd fixed number2, 4, 6, 8 (+2)
GeometricMultiply fixed number2, 6, 18, 54 (×3)
Squaresn²1, 4, 9, 16

Compare types to spot the right one fast

★

Key takeaway

Like choosing a basketball play: arithmetic for steady steps, geometric for big jumps!

SECTION 8

Connection to Advanced Patterns

Middle LevelAdvanced (High School)
Spot by differences or ratiosInfinite sums (series)
Next few termsGeneral formula aₙ

Master these now for harder tests later. Your pattern skills grow strong!

SECTION 9

Practice Problems

Question 1: CONCEPTUAL

What rule fits 1, 3, 5, 7? A) ×2 B) +2 C) +1 D) −2 E) Squares
Show answer
B) +2 is correct. Each adds 2 (odd numbers). A wrong—no multiply. C too small. D subtracts. E are 1²=1 but 3≠2².

Question 2: BASIC CALCULATION

Next in 5, 10, 15, 20? A) 22 B) 25 C) 30 D) 35 E) 40
Show answer
B) 25 (+5 each). 20+5=25. A skips. C doubles. D too much. E way off.

Question 3: INTERMEDIATE

Next in 2, 4, 8, 16? A) 18 B) 24 C) 32 D) 20 E) 64
Show answer
C) 32 (×2). 16×2=32. A adds. B adds 8. D halves. E ×4.

Question 4: APPLIED

Students: 10, 13, 17, 22. Next? A) 26 B) 27 C) 28 D) 29 E) 30
Show answer
C) 28 (+3, +4, +5, so +6=28). Differences grow by 1. A too small. B/D close but wrong. E over.

Question 5: CRITICAL THINKING

Shape rows: 1 dot, 4 dots, 9 dots. Next? A) 12 B) 14 C) 16 D) 18 E) 25
Show answer
C) 16 (squares: 1²,2²,3²,4²). A linear. B wrong. D not square. E too big (5²).

SUMMARY

Lesson Summary

Summary

Master pattern reasoning by checking differences or ratios. Use formulas like aₙ = a₁ + (n−1)d for steady adds.

Visuals and practice build your skill. You are ready for SSAT success—keep spotting those rules!

Varsity Tutors • SSAT Middle Level • Use pattern reasoning to predict a later term.