All example lessons

Maths · Free sample lesson

Writing & Simplifying Ratios

Write a ratio from a description or picture and simplify it using common factors.

  • About 25 minutes
  • Ages 11+

Tonight's destination

Fumblebrew's Tower

Writing & Simplifying Ratios

0/7 sections · 0%

01Story opener

Story

Fumblebrew's Tower

The top of the alchemy tower: a bench crowded with glowing vials, twin measuring spoons, a silver dropper, a great measuring flask on a brass balance, a golden ladle hung above the cauldron, maps and an hourglass on the shelf.

Order matters, and both parts scale together. Earn the twin measuring spoons.

Professor Fumblebrew
Two parts blue to three parts green — two to three! Four to six? Same brew, my assistant!
02
Core Concept

Key Concepts

Writing a Ratio

A ratio compares parts: 2 spoons blue to 3 spoons green is 2 : 3, read two to three. The order follows the words: blue : green = 2 : 3, so green : blue = 3 : 2 — a different ratio. Count each part, write them in order with a colon.
Writing a Ratio

Simplifying

Ratios simplify like fractions: divide every part by the same common factor. 4 : 6 → ÷ 2 → 2 : 3. 12 : 18 → ÷ 6 → 2 : 3. 10 : 15 : 25 → ÷ 5 → 2 : 3 : 5. Simplest form has no common factor but 1. Equivalent ratios describe the same mixture.
Simplifying

Order and the Part-Whole Trap

2 : 3 means 2 parts to 3 parts — 5 parts in all. So blue is 2/5 of the mixture, not 2/3. The trap is turning 2 : 3 into the fraction ⅔ — that compares blue to green, not blue to the whole. And never swap the order: 3 : 2 is a different, greener brew.
Order and the Part-Whole Trap
03
Guided Practice

Fill in the Missing Values

Work through each question carefully. Take your time.

Filled 0 of 40% Complete
2 spoons blue to 3 spoons green is written Drop here.
4 : 6 simplifies to Drop here.
12 : 18 simplifies to Drop here.
2 spoons blue to 3 spoons green, in the ratio 2 : 3, blue is Drop here of the mixture.
Answer Bank

Tap or drag a word into a gap. Tap a placed word to send it back.

2 : 32 : 32 : 32/5
04
Guided Practice

Match the Pairs

Work through each question carefully. Take your time.

0 of 5 pairs matched0% Complete
Matching Game5 pairs

Match the Pairs

Drag items from the left to match them with items on the right

Left Items

Right Items

05
Guided Practice

Knowledge Check

Work through each question carefully. Take your time.

Loading quiz...

06
Independent Practice

Brewing Challenge

Now it's your turn. Apply what you've learned on your own.

Loading quiz...

07
Recap

Well Done!

Written true, my assistant! Ratios in order, simplified by common factors, equivalent when scaled together — and 2 : 3 is 2 parts of 5, never two-thirds. The twin measuring spoons are yours. Next, scaling.

Like what you see?

Every lesson is built like this — story, instruction, interactive practice. Start your free trial to play the full library.