Three patients at a psychiatric clinic are up for release. The psychiatrist informs them that they will have to pass a simple test. He asks the first patient, "How much is two plus two?"

"Blue."

At which point the doctor calls in the orderly to escort the patient back to his room. Turning to the second patient, he asks, "What is six minus three?"

To which the patient replies, "Square."

Once again the orderly is called in to remove the patient. Turning to the third and last patient, he asks, "How much is five plus five?

The patient answers very confidently, "Ten."

The doctor, amazed, then inquires, "Very good. How did you figure it out?"

The patient reply, "Easy. Blue multiplied by square equals ten."