Most number tricks involve some math. This one definitely does:

Ask an audience member to select a number from 1 to 10.
Tell that person to do the following:
Multiply the selected number by 2.
Add 6 to that product.
Divide the sum by 2.
Subtract the original value of the card from that quotient.

Dramatically announce that the result is 3.

Why is the result always 3 no matter what number is selected? Write a variable expression or equation to model the number trick. (Hint: Use a variable for the selected number.) Then use your expression or equation to explain how the trick works.


Discussion Board Instructions
When you have finished, post your explanation of the number trick in the Analyze a Number Trick discussion board.
Remember to name your post with the title Choice A: How Does That Number Trick Work?