You will need:

- A brain

- the ability to do simple addition and subtraction

**Signing Up**

## Step 1: Step 1

## Step 4: Step 4

## Step 5: Step 5

**original number**they picked from their current total.

## Step 6: Step 6 finally!

**5**.

## Step 7: The Trick

The secret lies in Step 3 where you ask them to add a number.

You can pick any number divisible by 2 to be added.

**The final answer will always be the number you asked them to add in Step 3 divided by 2.**In this case I asked you to add

**10**to your total, hence your final answer was

**5**.

Good luck and have fun with this.