Mental Math · Division · D1

Break the dividend.

Division is just un-multiplying. To divide a big number, break it into friendly chunks that each divide evenly, divide each chunk, then add the results: 96 ÷ 4 = 80÷4 + 16÷4 = 20 + 4 = 24.

01 / THE METHOD

How to think about it.

Watch the method

Break the dividend

96 ÷ 4: split 96 into 80 and 16 — both divide by 4. 80÷4 = 20, 16÷4 = 4, and 20 + 4 = 24.

1 / 4

96 \div 4

= ?

96 = 80 + 16

Split 96 into two parts that both divide by 4.

80 \div 4 = 20

Divide the big chunk.

16 \div 4 = 4

Divide the rest.

20 + 4 = 24

Add the two answers.

02 / YOUR TURN

Practice until it feels easy.

Your turn

Solve it in your head.

Use the method, then check. Stuck? Reveal the steps.

streak 0

best 0

… =

— / WHY IT WORKS

The idea underneath.

Divide the parts, add the answers

Just like multiplication breaks numbers apart, so does division. Choose chunks that divide your divisor cleanly (often a round multiple of it), divide each, and add.

Why it works

Sharing 96 cookies among 4 friends: hand out 80 (20 each), then the last 16 (4 each).

03 / WORKED EXAMPLES

From easy to tricky.

EX 1easy

84 ÷ 6

Split

84 = 60 + 24.

Divide each

60÷6 = 10, 24÷6 = 4.

Add

10 + 4 = 14.

EX 2medium

96 ÷ 4

Split

96 = 80 + 16.

Divide each

80÷4 = 20, 16÷4 = 4.

Add

20 + 4 = 24.

EX 3hard

252 ÷ 9

Split

252 = 180 + 72.

Divide each

180÷9 = 20, 72÷9 = 8.

Add

20 + 8 = 28.

04 / COMMON TRAPS

Where students slip.

Trap

Splitting into chunks that don't divide evenly.

Fix

Pick chunks that each divide by the divisor. For ÷4, use multiples of 4 like 80 and 16 — not 90 and 6.

Trap

Forgetting to add the chunk answers.

Fix

Each chunk gives part of the answer. 20 and 4 must be added: 24.

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)

96 ÷ 4 = ?

Need a hint?

Split the number into chunks that each divide evenly.
Divide each chunk, then add the answers.

84 ÷ 6 = ?

Need a hint?

Split the number into chunks that each divide evenly.
Divide each chunk, then add the answers.

78 ÷ 3 = ?

Need a hint?

Split the number into chunks that each divide evenly.
Divide each chunk, then add the answers.

90 ÷ 5 = ?

Need a hint?

Split the number into chunks that each divide evenly.
Divide each chunk, then add the answers.

Apply

Apply (4)

96 ÷ 8 = ?

Need a hint?

Split the number into chunks that each divide evenly.
Divide each chunk, then add the answers.

144 ÷ 6 = ?

Need a hint?

Split the number into chunks that each divide evenly.
Divide each chunk, then add the answers.

138 ÷ 6 = ?

Need a hint?

Split the number into chunks that each divide evenly.
Divide each chunk, then add the answers.

175 ÷ 5 = ?

Need a hint?

Split the number into chunks that each divide evenly.
Divide each chunk, then add the answers.

Extension

Extension (4)

224 ÷ 7 = ?

Need a hint?

Split the number into chunks that each divide evenly.
Divide each chunk, then add the answers.

192 ÷ 8 = ?

Need a hint?

Split the number into chunks that each divide evenly.
Divide each chunk, then add the answers.

252 ÷ 9 = ?

Need a hint?

Split the number into chunks that each divide evenly.
Divide each chunk, then add the answers.

168 ÷ 6 = ?

Need a hint?

Split the number into chunks that each divide evenly.
Divide each chunk, then add the answers.