Logical Questions

Thinking Out of the Box

1. Water Jug Problem

You are next to a river, and you are given a very big jar, and 4L & 3L jugs.
You need to fill 5 liters of water in the large jar.

  • How many ways?
  • Find more than one way?

Examples:

  • 5 = 4 + (4 - 3)
  • 5 = 4 + 4 → total 8 in big jar → 8 - 3 = 5

2. Cake Cutting Problem

How to cut a cake into 8 pieces with 3 cuts, without moving the pieces?

  • The cake is cubic in shape.
  • Solution:
    • Make 2 cuts on the top (cross)
    • Then 1 horizontal cut in the middle (half-cut from the side)

3. Water Tank Problem

There is a water tank where every second its water level doubles.
It takes 30 seconds to reach full level (100%).

Question: How much time is required to reach quarter level (25%)?

  • At 30 sec = 100%
  • At 29 sec = 50%
  • At 28 sec = 25%

✅ Answer: 28 seconds