This display is sure to get people thinking, you can create any pattern you like and make it as simple or advanced as you like. There are two versions the main one says: "If __ is ___. What is ___?" The alternative is worded slightly differently (it's more for beginners)
"If __ is equal to ___. What is ___?"
Use it for base 8 math to "If B=C what is E?" (Ans. D)
Kids and grown ups love this one!