🧠 Logical Thinking Challenges — Part 2

Shant Khayalian — Balian’s IT

💡 Test Your Mind with These 5 Brain Teasers!

Each problem will: ✅ Start with a real-life scenario ✅ Challenge you to think logically ✅ Provide a detailed solution with explanations

🔥 The Five Challenges

1️⃣ The Missing Taxi Mystery 🚕

🔍 The Problem:

Bob is standing on a busy city street, trying to hail a taxi. He sees 20 taxis drive by, but when he tries to count them, he always ends up with only 19.

❓ Where did the missing taxi go?

Shant Khayalian — Balian’s IT

✅ The Solution:

Bob is unknowingly counting the same taxi twice!

✔ The trick? Some taxis are circling back around the block before Bob finishes counting, so he counts one of them twice without realizing it.

📌 Key Lesson: When dealing with real-world data, always consider the possibility of overlapping counts or repetitions!

2️⃣ The Trapped Elevator Puzzle 🏢

🔍 The Problem:

Alice lives on the top floor of a 100-story building. The elevator is broken, and she can only:

• Go up 5 floors at a time
• Go down 3 floors at a time

She starts on the ground floor (0). How many times does she need to press the buttons to reach the 100th floor?

Shant Khayalian — Balian’s IT

✅ The Solution:

For every one full cycle (Up 5 → Down 3), Alice gains 2 floors.

✔ To reach 100 floors:

1002=50 cycles\frac{100}{2} = 50 \text{ cycles}2100​=50 cycles

Final Answer: 50 presses to reach the top!

📌 Key Lesson: Breaking down patterns into cycles helps simplify complex problems.

3️⃣ The Magic Bank Account 💰

🔍 The Problem:

Bob’s bank has a strange rule:

• Every day, the bank doubles Bob’s money.
• Every night, Bob spends $200.
• Bob starts with $100.

❓ How much money will Bob have after 5 days?

Shant Khayalian — Balian’s IT

✅ The Solution:

Day-by-day breakdown:

Bob never makes it past Day 2 because his balance reaches $0 on the first night, and doubling zero still equals zero.

📌 Key Lesson: Don’t assume patterns always continue — test early steps to check for failure cases!

4️⃣ The Speed Limit Dilemma 🚗

🔍 The Problem:

Bob is driving 100 km to visit Alice.

• He drives 50 km at 50 km/h.
• How fast must he drive the next 50 km to average 100 km/h for the entire trip?

Shant Khayalian — Balian’s IT

✅ The Solution:

✔ Total Distance = 100 km ✔ Total Time Needed (to average 100 km/h) = 1 hour

Bob already spent:

5050=1 hour\frac{50}{50} = 1 \text{ hour}5050​=1 hour

❌ No time left for the next 50 km!

Final Answer: 🚨 It’s impossible!

📌 Key Lesson: Check time constraints before assuming something is possible!

5️⃣ The Mismatched Socks Problem 🧦

🔍 The Problem:

Bob has a drawer with 10 red socks, 10 blue socks, and 10 green socks.

❓ What is the minimum number of socks Bob must pull out blindly to guarantee he gets at least one matching pair**?

💡 Cartoon Illustration Prompt:

Shant Khayalian — Balian’s IT

✅ The Solution:

In the worst case, Bob could pick one of each color: 1️⃣ Red sock 2️⃣ Blue sock 3️⃣ Green sock

If he picks one more sock, it must match one of the previous three!

Final Answer: 4 socks guarantee a matching pair!

📌 Key Lesson: When solving worst-case problems, assume the worst possible outcome and work from there.

🏆 Challenge Recap: What You Learned

Did you solve them before checking the answers? 😃

🚀 Want More? Part 3 Coming Soon!

Next time, we’ll increase the difficulty with puzzles involving logic gates, time paradoxes, and real-world optimization problems!

💡 Want Part 3? Drop a comment or message me!

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