There was a logic question that consisted of creating a scenario, where there were pieces of paper with a number on one side of the paper and a letter on the other side. There were four different pieces of paper: one with an X and another with a Y. The other two have a 1 and 2 on it respectively. My interviewer then gave me the assertion "On the back of every paper with an X, there is an even number" I was then asked which pieces of paper I needed to flip over in order to prove the assertion.