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Zero factorial equals ONE. Not zero. ONE. Here's the proof.

Most people assume 0! = 0. But it's actually 1, and the reason is beautiful.

Step 1: What IS factorial?
n! means multiply all the way down to 1.
5! = 5 × 4 × 3 × 2 × 1 = 120
4! = 4 × 3 × 2 × 1 = 24
3! = 3 × 2 × 1 = 6
2! = 2 × 1 = 2
1! = 1

Step 2: Spot the pattern → n! = n × (n-1)!
4! = 4 × 3! → 4 × 6 = 24 ✅
3! = 3 × 2! → 3 × 2 = 6 ✅
2! = 2 × 1! → 2 × 1 = 2 ✅

Step 3: Now walk BACKWARDS.
We know: 1! = 1
By the rule: 1! = 1 × 0!
So: 1 = 1 × 0!
Divide both sides by 1 → 0! = 1 ✅

It HAS to be 1. Any other value breaks the entire pattern.

💡 Bonus: 0! = 1 is also why combinations work — the number of ways to choose 0 items from n items is 1 (choose nothing).

❓ Did you think 0! was 0? Be honest! Comment below! 👇

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🎲 Pick ANY 3-digit number. The answer is ALWAYS 1089.

Here's how it works — let's try with 732:

Step 1: Pick a 3-digit number → 732 (first and last digits must differ)

Step 2: Reverse the digits → 237

Step 3: Subtract the smaller from the larger → 732 − 237 = 495

Step 4: Reverse the result → 594

Step 5: Add them up → 495 + 594 = 1089 ✅

Try it with 521:
521 → 125 → 521 − 125 = 396 → 693 → 396 + 693 = 1089 ✅

Try it with 943:
943 → 349 → 943 − 349 = 594 → 495 → 594 + 495 = 1089 ✅

It works EVERY. SINGLE. TIME. No matter what 3-digit number you pick (as long as the first and last digits are different).

💡 Bonus fact: 1089 × 9 = 9801 — that's 1089 flipped backwards!

❓ What number did you try? Did it work? Comment below! 👇

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🤯 Can you make 10 using only four 3s and any mathematical operations?

Most people try addition and multiplication first:
❌ 3 + 3 + 3 + 3 = 12 (too big!)
❌ 3 × 3 + 3 − 3 = 9 (too small!)

But here's the trick — think in fractions! 💡

Step 1: Write it out → 3 × 3 + ³⁄₃ = ?
Step 2: Multiply → 3 × 3 = 9
Step 3: Divide → ³⁄₃ = 1
Step 4: Add → 9 + 1 = 10 ✅

The key insight? ³⁄₃ = 1. Once you see that, the rest falls into place!

Which number should we tackle next? Comment below! 👇

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t² = 2³² looks impossible — until you see the trick 🧮

Most students freeze at 2³². But here's the key: when you take the square root, the exponent gets cut in half. √(2³²) = 2^(32÷2) = 2¹⁶. That's it — the power does the work for you.

Don't forget the ± sign! Every square root gives TWO answers: t = +65,536 AND t = −65,536. Missing the negative root is the #1 mistake examiners catch.

Save this for your next exam! 📌

Double-tap if you learnt something! ❤️

NCERT Class 4 Maths Ch-1 | Building Model Parts — Roof, Pillars & Base | Shapes Around Us

🎓 Ever wondered what makes a building model look just like the real thing? In this video, we explore the key parts of a building model — roof, pillars, base, walls, and entrance — and understand why these features matter! Perfect for NCERT Class 4 Maths Chapter 1: Shapes Around Us.

📌 WHAT YOU'LL LEARN
- Identify the main parts of a building model
- Understand what roof, pillars, base, walls and entrance represent
- Learn why certain parts are selected for a model
- Connect 3D shapes to real-world structures
- Describe building models using correct vocabulary
- Relate Diksha's India Gate model example to your own models
- Recognize visible and recognizable features of buildings
- Answer NCERT textbook short answer questions confidently
- Build observation skills by looking at structures around you

🎯 KEY CONCEPTS COVERED
- Building model parts identification
- Roof as the top covering structure
- Pillars as vertical support columns
- Base as the foundation of the model
- Walls as enclosing side structures
- Entrance as the opening feature
- Visible and recognizable building features
- 3D shapes in real-world structures
- Diksha's India Gate model example from NCERT
- Connecting models to actual buildings

💡 PERFECT FOR
- Class 4 CBSE students studying Shapes Around Us
- Students preparing for NCERT Maths Chapter 1
- Learners curious about 3D shapes and building models
- Parents helping kids with homework and revision
- Teachers looking for classroom explanation resources

🎨 VISUAL LEARNING
We use colorful animations to show each part of a building model — from the roof at the top to the base at the bottom. Watch as pillars, walls, and entrance come to life, making it easy to remember and identify each component. The India Gate model example is recreated step by step!

⚠️ COMMON MISTAKES TO AVOID
- Forgetting to mention all five key parts: roof, pillars, base, walls, entrance
- Confusing pillars with walls
- Not explaining WHY these parts are chosen
- Leaving out the base or foundation
- Writing vague answers without naming specific parts
- Missing the connection between model parts and real building features

📚 THE PROBLEM/CONCEPT BREAKDOWN
1. Read the question carefully — it asks for parts shown in YOUR model
2. Identify each part: roof (top cover), pillars (vertical supports), base (bottom foundation), walls (side enclosures), entrance (opening)
3. List all visible and recognizable features
4. Explain the reason: these parts make the model look similar to the real building
5. Write a complete answer naming all parts with brief descriptions

🌟 WHY THIS VIDEO IS DIFFERENT
We don't just list the parts — we show you WHY each part matters using visual examples and Diksha's India Gate model. This makes remembering and writing answers in exams much easier!

👨‍🏫 ABOUT APARSOFT
Aparsoft by Apar Academy creates engaging, curriculum-aligned educational content for CBSE students. Our videos simplify complex concepts with animations and step-by-step explanations aligned to NCERT textbooks. Visit https://aparacademy.com for more resources.

💬 COMMENT BELOW
Which part of a building model do you find most interesting? Have you ever made a building model yourself? What other parts can you think of that we missed? Tell us in the comments!

📌 STUDY TIPS
1. Draw a simple building and label each part — roof, pillars, base, walls, entrance
2. Look at real buildings around you and identify these parts
3. Practice writing the answer in your own words
4. Use Diksha's India Gate example to remember the concept
5. Revise by explaining the parts to a friend or family member

🔔 If this video helped you, LIKE, SUBSCRIBE and hit the bell icon for more NCERT Class 4 Maths videos! Share with friends who need help with Shapes Around Us!



https://youtu.be/Zv6GEtV7qwM

NCERT Class 4 Maths Ch-1 | Building Model Parts — Roof, Pillars & Base | Shapes Around Us 🎓 Ever wondered what makes a building model look just like the real...