# Interview Questions

You are blindfolded and 10 coins are place in front of you on table. 5 are having their heads-side up and 5 are having their tails-side facing upward.

You cannot tell which way they are by touching the coin.

You are allowed to touch the coins and flip them as many times as you want.

How do you make two piles of coins each with the same number of heads-up and tails-up?

**Solution:**

This may sound like a difficult puzzle, but the solutions is very simple, You can arrive at the same solution by doing some trial-n-error.

1. Make two piles with equal number of coins (5 each) 2. Flip all the coins in one of the piles.

After doing above two steps, the number of heads-up and tails-up in both the heap will be same.

Let’s see some examples. Let us assume that we always flip the coins in first pile:

Input Piles : H T T T T, T H H H H Output Piles: T H H H H, T H H H H ------------------------------------- Input Piles : H H T T T, T T H H H Output Piles: T T H H H, T T H H H

Similarly, you may try any combination but the result will be same.