01 / THE IDEA

See it work.

Watch the method

Reduce step by step

12/18 → ÷2 → 6/9 → ÷3 → 2/3.

1 / 2

\frac{12}{18}

1

Find a common factor

12 and 18 both divide by 6.

\gcd(12,18)=6

2

Divide top and bottom

Divide both by 6.

\frac{12}{18} = \frac{2}{3}

02 / YOUR TURN

Practice until it feels automatic.

Your turn

Work it out.

Type a fraction like 3/4 or 1 1/2.

streak 0

best 0

… =

— / WHY IT WORKS

The idea underneath.

Lowest terms

A fraction is in lowest terms when the only common factor of top and bottom is 1.

Why it works

Keep grouping the slices until you cannot group further.

03 / WORKED EXAMPLES

From easy to tricky.

EX 1easy

Simplify 16/28

1

Find a common factor

16 and 28 both divide by 4. \gcd(16,28)=4

2

Divide top and bottom

Divide both by 4. 16/28 = 4/7

EX 2medium

Simplify 12/20

1

Find a common factor

12 and 20 both divide by 4. \gcd(12,20)=4

2

Divide top and bottom

Divide both by 4. 12/20 = 3/5

EX 3hard

Simplify 24/36

1

Find a common factor

24 and 36 both divide by 12. \gcd(24,36)=12

2

Divide top and bottom

Divide both by 12. 24/36 = 2/3

04 / COMMON TRAPS

Where students slip.

Trap

Thinking one division is always enough.

Fix

Check again — there may be more.

Trap

Believing the value changed.

Fix

Reducing keeps the same value.

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

Simplify 16/28

Need a hint?

Divide by a common factor.
Repeat until none is left.

C2

Simplify 4/24

Need a hint?

Divide by a common factor.
Repeat until none is left.

C3

Simplify 5/35

Need a hint?

Divide by a common factor.
Repeat until none is left.

C4

Simplify 9/12

Need a hint?

Divide by a common factor.
Repeat until none is left.

Apply

Apply (4)

A1

Simplify 12/20

Need a hint?

Divide by a common factor.
Repeat until none is left.

A2

Simplify 12/16

Need a hint?

Divide by a common factor.
Repeat until none is left.

A3

Simplify 4/12

Need a hint?

Divide by a common factor.
Repeat until none is left.

A4

Simplify 18/24

Need a hint?

Divide by a common factor.
Repeat until none is left.

Extension

Extension (4)

E1

Simplify 24/36

Need a hint?

Divide by a common factor.
Repeat until none is left.

E2

Simplify 8/20

Need a hint?

Divide by a common factor.
Repeat until none is left.

E3

Simplify 9/21

Need a hint?

Divide by a common factor.
Repeat until none is left.

E4

Simplify 10/35

Need a hint?

Divide by a common factor.
Repeat until none is left.

Reduce step by step.