Integers · Add integers · 4.6

Adding in context.

Real changes are integer additions: a temperature rising, a balance after a deposit and a withdrawal, a diver ascending. Translate the story, then add.

01 / THE IDEA

See it work.

Watch the method

Adding in context

−6 °C rising 10° → −6 + 10 = 4 °C.

1 / 2
−6+10-6 + 10
1

Different signs — subtract

Subtract the smaller size from the larger: 10 − 6.

10−6=410 - 6 = 4
2

Take the bigger sign

10 is the larger size and it is positive, so the answer is positive.

−6+10=4-6 + 10 = 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.

Story to sum

Up/gain/deposit is positive; down/loss/withdrawal is negative. Add them.

Why it works

From −6 °C, a 10° rise lands at 4 °C.

03 / WORKED EXAMPLES

From easy to tricky.

EX 1easy

Add -12 + 5

1

Different signs — subtract

Subtract the smaller size from the larger: 12 − 5. 12 - 5 = 7

2

Take the bigger sign

12 is the larger size and it is negative, so the answer is negative. -12 + 5 = -7

EX 2medium

Add 6 + -11

1

Different signs — subtract

Subtract the smaller size from the larger: 11 − 6. 11 - 6 = 5

2

Take the bigger sign

11 is the larger size and it is negative, so the answer is negative. 6 + (-11) = -5

EX 3hard

Add 10 + -11

1

Different signs — subtract

Subtract the smaller size from the larger: 11 − 10. 11 - 10 = 1

2

Take the bigger sign

11 is the larger size and it is negative, so the answer is negative. 10 + (-11) = -1

04 / COMMON TRAPS

Where students slip.

Trap

Ignoring the starting sign.

Fix

Begin from the signed start value.

Trap

Treating a loss as positive.

Fix

Losses and drops are negative.

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

Add -12 + 5

Need a hint?
  • Write the start with its sign.
  • Add the signed change.
C2

Add -12 + 3

Need a hint?
  • Write the start with its sign.
  • Add the signed change.
C3

Add -6 + 10

Need a hint?
  • Write the start with its sign.
  • Add the signed change.
C4

Add 10 + -10

Need a hint?
  • Write the start with its sign.
  • Add the signed change.
Apply

Apply (4)

A1

Add 6 + -11

Need a hint?
  • Write the start with its sign.
  • Add the signed change.
A2

Add 2 + -8

Need a hint?
  • Write the start with its sign.
  • Add the signed change.
A3

Add -1 + 9

Need a hint?
  • Write the start with its sign.
  • Add the signed change.
A4

Add -5 + 1

Need a hint?
  • Write the start with its sign.
  • Add the signed change.
Extension

Extension (4)

E1

Add 10 + -11

Need a hint?
  • Write the start with its sign.
  • Add the signed change.
E2

Add -10 + 6

Need a hint?
  • Write the start with its sign.
  • Add the signed change.
E3

Add -9 + 4

Need a hint?
  • Write the start with its sign.
  • Add the signed change.
E4

Add 11 + -9

Need a hint?
  • Write the start with its sign.
  • Add the signed change.