Integers · Compare & order · 2.3

Before & after.

Every integer has a predecessor (one less, a step left) and a successor (one more, a step right). The integer just before −3 is −4; just after is −2.

01 / THE IDEA

See it work.

On the number line

Start at 0, hop right 0.

0 + 0 = 0

-1010

Watch the method

Before & after

Just before −3 is −4 (one step left).

1 / 1
?  →(−3)?\; \to (-3)
1

One step on the line

The predecessor is one step to the left (−1).

(−3)−1=−4(-3) - 1 = -4
02 / YOUR TURN

Practice until it feels automatic.

Your turn

Work it out.

Type a whole number — negatives allowed, e.g. -7.

streak 0
best 0
… =
— / WHY IT WORKS

The idea underneath.

Neighbours on the line

Predecessor = subtract 1; successor = add 1. There are no integers in between.

Why it works

The next notch on the ruler.

03 / WORKED EXAMPLES

From easy to tricky.

EX 1easy

Which integer comes just before 10?

1

One step on the line

The predecessor is one step to the left (−1). 10 - 1 = 9

EX 2medium

Which integer comes just before 10?

1

One step on the line

The predecessor is one step to the left (−1). 10 - 1 = 9

EX 3hard

Which integer comes just after 5?

1

One step on the line

The successor is one step to the right (+1). 5 + 1 = 6

04 / COMMON TRAPS

Where students slip.

Trap

Thinking −4 comes after −3.

Fix

−4 is before (less than) −3.

Trap

Jumping more than one step.

Fix

Neighbours differ by exactly 1.

05 / QUIZ

Test yourself.

The Test

12 problems across three tiers. Auto-graded on submit. Hints and a full walkthrough on every question. Your work is saved on this device — sign in to keep it across devices.

0/12Answered
How to answerType just the value. Formatting won't trip you up — we ignore spaces, capital letters, commas, and subscript style, so t₁ = 5, d = 3 and t1=5,d=3 both count. For a list of numbers, separate them with commas (e.g. 3, 10, 17).
Core

Core (4)

C1

Which integer comes just before 10?

Need a hint?
  • “Just before” = one step left (−1).
  • “Just after” = one step right (+1).
C2

Which integer comes just before -5?

Need a hint?
  • “Just before” = one step left (−1).
  • “Just after” = one step right (+1).
C3

Which integer comes just after 10?

Need a hint?
  • “Just before” = one step left (−1).
  • “Just after” = one step right (+1).
C4

Which integer comes just after -2?

Need a hint?
  • “Just before” = one step left (−1).
  • “Just after” = one step right (+1).
Apply

Apply (4)

A1

Which integer comes just before 10?

Need a hint?
  • “Just before” = one step left (−1).
  • “Just after” = one step right (+1).
A2

Which integer comes just after 2?

Need a hint?
  • “Just before” = one step left (−1).
  • “Just after” = one step right (+1).
A3

Which integer comes just before -4?

Need a hint?
  • “Just before” = one step left (−1).
  • “Just after” = one step right (+1).
A4

Which integer comes just after 12?

Need a hint?
  • “Just before” = one step left (−1).
  • “Just after” = one step right (+1).
Extension

Extension (4)

E1

Which integer comes just after 5?

Need a hint?
  • “Just before” = one step left (−1).
  • “Just after” = one step right (+1).
E2

Which integer comes just before 1?

Need a hint?
  • “Just before” = one step left (−1).
  • “Just after” = one step right (+1).
E3

Which integer comes just after -4?

Need a hint?
  • “Just before” = one step left (−1).
  • “Just after” = one step right (+1).
E4

Which integer comes just before 2?

Need a hint?
  • “Just before” = one step left (−1).
  • “Just after” = one step right (+1).