Logic problems require critical thinking and deduction skills. Usually, they do not require pure mathematics skills. For many students, there are the most fun types of problems. Let’s look at an example:

• There are three doors. On each one of them, there is a sign. There is a lion behind one of the doors and endless treasures behind the other two. The first sign says, “There is no lion here.” The second sign also says, “There is no lion here.” The third sign says, “The lion is behind door 1.” Only one of the signs is telling the truth. Where is the lion?

Let’s say the lion is behind door 1. That would mean that sign 1 would be lying and signs 2 and 3 would be telling the truth. So, the lion cannot be behind door 1.

Let’s try door 2. If the lion was here, that would mean sign 1 is telling the truth and sign 2 is lying. Since sign 1 is telling the truth, sign 3 would be lying. There is only 1 sign that is telling the truth, so this is where the lion is.

We already know where the lion is, but let’s try door 3 just to make sure we are right. If the lion was behind door 3, signs 1 and 2 would be telling the truth. Additionally, sign 3 would be lying. Since there are two signs telling the truth, the lion cannot be behind door 3.

• Four students have lunch at different times: 11:30, 12:00, 12:30, and 1:00. Ana eats before Leo, Zoe eats after Sam, and Leo eats at 12:00. Arrange their lunch order.

We know that Leo eats at 12:00. Since Ana eats before Leo, she has to eat at 11:30 because that is the only time slot before 12:00. The two remaining times are 12:30 and 1:00. Since Zoe eats after Sam, he has to eat at the earlier of the remaining times, which is 12:30. Thus, Zoe eats the latest, which is 1:00.

The final order is Ana, Leo, Sam, and Zoe.

• Just for fun: What is the next term in the sequence: 3, 3, 5, 4, 4, _ (try to solve it before looking at the explanation.)

If you thought this sequence didn’t make sense, you are right. This not is a mathematical sequence, but there is a right answer. The 1st term has a value of three. The word “one” has three letters. The 2nd term has a value of 3. “Two” has three letters. So, the 6th and final term has to equal 3, since “Six” has 3 letters.