The short answer to how many questions there are on the MAT is 120. But there’s also more to take into consideration.
The long answer
The exam you will take presents 120 analogy questions for you to solve in 60 minutes. These range across multiple subjects and represent 4 main types of relationships (though these are broken down into smaller categories that can be recognized). Analogies seem simple but actually represent very complex ideas, you will probably use most or all of the 60 minutes allotted.
However (yes, there’s always a but), of those 120 questions, only 100 of them count towards your score. The other 20 are experimental questions that Pearson is trying out to see if they will be good questions to put on future tests. The kicker is, you won’t know which questions are experimental and which are not. It’s best to treat every question as though it is important. In contrast, don’t stress out if you really can’t figure out a problem; one question is not going to make or break the test or ruin your score.
I recommend that you take practice tests in a quiet place as closely simulating the testing environment as possible. Whether it’s the complexity of the concept or a lack of familiarity with a subject, there are going to be questions that take more time than others to answer. Some you will breeze right through and others will stump you. The key is to balance your attention so that you can confidently answer the questions you are sure of but not let a difficult one bog you down. Practicing the 120 questions in 60 minutes will give you a good feel of your answering rhythm. Remember, you can skip a question that is bothering you and go back to it when you know you have more time.