Round Table Coin Game | Puzzles for Interview - Interview Preparation PDF Download

Introduction

In this game, the goal is to place the numbers 1 to 9 in a circle so that whenever there are three in a straight line, they add up to 15. Here's how to do it:

Step 1: Start with the first and last numbers. The sum of 1 and 9 is 10, so place these two numbers opposite each other on the circle.

Step 2: Move to the second and second-to-last numbers. The sum of 2 and 8 is also 10, so place these two numbers opposite each other on the circle as well.

Step 3: Repeat this process with the third and seventh numbers, and the fourth and sixth numbers. These four pairs (1, 9), (2, 8), (3, 7), and (4, 6) should occupy the external circles or places.

Step 4: Place the number 5 in the center of the circle.

Step 5: Make sure that each pair of opposite numbers adds up to 10. This means that 1 should be placed opposite to 9, 2 opposite to 8, 3 opposite to 7, and 4 opposite to 6.

Step 6: Check that each straight line of three numbers adds up to 15. You should have four lines that add up to 15: 1-9-5, 2-8-5, 3-7-5, and 4-6-5.

Congratulations, you have solved the Round Table Coin Game!