1. How many golf balls can fit in a school bus?
Hint: Estimate volume of a golf ball and a bus, then divide.
2. How much should you charge to wash all the windows in Seattle?
Hint: Flat rate per window, focus on scalable solution.
3. Why are manhole covers round?
Answer: Because a round cover won’t fall into the hole.
4. How many piano tuners are there in the entire world?
Hint: Use logical assumptions based on population and demand.
5. You have a 100-story building. How would you find the highest floor you can drop an egg without breaking it?
Hint: Minimize drops using binary search method.
6. Design an evacuation plan for San Francisco.
Hint: Think high-level logistics, traffic flow, critical resources.
7. How would you explain the internet to a 5-year-old?
Hint: Use simple analogies like a “magic library” or “invisible post office.”
8. How many times a day do a clock’s hands overlap?
Answer: 22 times in 24 hours.
9. Estimate the number of gas stations in the United States.
Hint: Assume cars per person, average usage, gas station capacity.
10. If you were shrunk to the size of a nickel and dropped into a blender, what would you do?
Answer: Jump out before it starts or use physics (spring action).
11. How many hairs are there on a human head?
Hint: Average 100,000–150,000 hairs per person.
12. What is the next number in the sequence: 10, 9, 60, 90, 70, 66, ___?
Answer: 96 (based on spelling the numbers).
13. How many basketballs would fit in this room?
Hint: Find room volume / basketball volume.
14. You’re given two ropes. Each rope takes an hour to burn, but not at a consistent rate. How can you measure 45 minutes?
Answer: Light both ends of one rope and one end of the other.
15. If you look at a clock and the time is 3:15, what’s the angle between the hour and minute hands?
Answer: 7.5 degrees.
16. Why are tennis balls fuzzy?
Answer: Improves aerodynamic stability and player control.
17. If you had a stack of pennies as tall as the Empire State Building, how many pennies would there be?
Hint: Estimate building height and penny thickness.
18. How would you move Mount Fuji?
Hint: Think metaphorically — reframe the problem.
19. Design a spice rack for a blind person.
Hint: Focus on touch, Braille, shapes, and scent recognition.
20. You have 8 identical balls, but one is slightly heavier. Find the heavier ball using a balance scale only twice.
Hint: Divide and conquer groups smartly.
21. How would you test a calculator?
Hint: Normal cases, boundary tests, unusual inputs.
22. Why does a mirror reverse left and right but not up and down?
Answer: Mirrors reverse depth, not left/right.
23. How do you estimate the weight of the Empire State Building?
Hint: Volume Ă— material density approximation.
24. How many ways can you find a needle in a haystack?
Answer: Burn it, use a magnet, use sieves.
25. Design a better vending machine.
Hint: Focus on user experience, security, speed, mobile payment.
26. If you could remove one U.S. state, which would it be and why?
Hint: No wrong answer, judge critical thinking.
27. What is the most creative way you can break a clock?
Hint: Think outside the box: deconstruct time, sabotage mechanics.
28. How would you solve homelessness in a big city?
Hint: Policy ideas + practical, scalable actions.
29. Why are soda cans shaped the way they are?
Answer: Efficient stacking, pressure resistance, material economy.
30. How would you design an alarm clock for the deaf?
Hint: Vibration, flashing lights, wearable tech.
31. What do you think of Google’s product design?
Hint: Focus on minimalism, functionality, scalability.
32. What’s the fastest way to sort a million integers?
Hint: Use quicksort or a more advanced sorting method based on constraints.
33. If you could be remembered for one thing, what would it be?
Hint: Authentic and value-driven answer.
34. Explain a database in three sentences to your eight-year-old nephew.
Answer: It’s like a giant magic notebook. You write down lots of important stuff. Later, you can quickly find exactly what you need.
35. You have a 3-gallon and a 5-gallon jug. How do you measure exactly 4 gallons?
Hint: Fill 5-gallon, pour into 3-gallon, repeat process.