# How the Central Limit Theorem affects your studies

The Central Limit Theorem (CLT) states that most variables tend to cluster around a mean of 50% when you measure them in groups. So, if you take test papers, half will likely have the right questions. The Central Limit Theorem is just one essential topic you’ll learn in school.

In today’s high-tech and STEM-centered world, businesses need professionals with solid backgrounds in statistics, for instance. As a result of the nature of today’s work environment, many people are returning to school for advanced degrees. For example, a **Masters in Applied Statistics** from Michigan Technological University ensures you will have the skills needed to navigate the modern business world.

Now, let’s assume you’re heading back to school to **advance your career**. Let’s take another look at the Central Limit Theorem and see how it could affect your studies.

**What does the Central Limit mean for test-taking?**

Assuming that your score is primarily the result of randomness, it shouldn’t be a massive cause for concern. The CLT is why you shouldn’t despair if your average score on a standardized test is around 50%. While that might seem low, it represents a high-performance level considering the number of people who take the test. A smaller percentage of people (e.g., 20% or less) will have a score within a specific range. That means although you weren’t the absolute best student in the class, according to the data, you don’t deserve a failing grade either.

**Calculating your mean and standard deviation**

The mean of a test gets calculated by taking the average of all the correct answers in **statistics**. Then you divide that number by the number of papers tested. So, if a test has 100 papers, the mean would be 50. If a test has 10 incorrect papers, the mean would still be 50. You should always calculate the standard of your test using correct and incorrect papers.

Now that you know how to calculate the mean, let’s move on to calculating the standard deviation. The standard deviation is the most commonly used statistic to determine how variable a given set of data is. It represents the average distance between all the data points and indicates whether a set of numbers is close to normal. The closer the data points are to the middle (i.e., the mean), and the wider that distance is, the more variable the data is.

**Final tips before you take your test**

Remember that whether you do well on a test is not directly related to your potential as a student. Many external factors decide how well you do. And that includes how much effort you put into your studies. For example, you won’t perform well if you’re sick during a test. That said, in most cases, your score won’t be that much lower than it would have been if that external factor weren’t present.

In sum, the Central Limit Theorem is a concept that affects everyone’s life. Most people don’t realize that the average score they receive on a test will likely fall in the “50” range. It may sound silly, but knowing this can help ease some of the stress of the situation.