Scale drawings: word problems

key notes :

📏 What is a Scale Drawing?

A scale drawing is a picture that shows a real object smaller or larger but keeps the same shape and proportions.

🔢 Understanding the Scale

A scale compares drawing size to real size.

Example: 1 cm = 5 m means every 1 cm on paper represents 5 m in real life.

🗺️ Common Uses of Scale Drawings

Maps 🗺️

Building plans 🏠

Classrooms and playground layouts 🏫

➗ Using Ratios

Scales are written as ratios like 1 : 100.

This means 1 unit on the drawing equals 100 units in real life.

✖️ Finding Real Length (Multiply!)

Real length = Drawing length × Scale factor

Example: If scale is 1 cm = 10 m, then 4 cm = 40 m

➖ Finding Drawing Length (Divide!)

Drawing length = Real length ÷ Scale factor

Example: 50 m ÷ 10 = 5 cm

📐 Same Shape, Same Angles

All angles in a scale drawing are equal to the real object’s angles.

🧠 Word Problem Tips

Read carefully 👀

Identify the scale

Decide: Multiply or Divide?

Write correct units (cm, m, km)

⚠️ Common Mistakes to Avoid

Mixing units (cm and m) ❌

Forgetting to use the scale ❌

Not writing the final unit ❌

🎯 Real-Life Example

A map uses a scale 1 cm = 2 km.

Distance on map = 6 cm

Real distance = 6 × 2 = 12 km 🚗

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✨ Quick Memory Trick

👉 Drawing → Real = Multiply ✖️
👉 Real → Drawing = Divide ➗

Learn with an example