Before taking an IQ test, most people ask the exact same question: "What exactly will I see?" The good news is that an IQ test does not test memorized facts. Instead, it measures how quickly you can solve a problem you have never seen before. You cannot really "study" for an IQ test, but knowing the underlying logic in advance keeps you from wasting time on surprises. Below, we cover six of the most common question types with an example and a step-by-step solution for each. If you want to see an overview of all question types, check out our article What Question Types Appear on an IQ Test?.
1. Number series: spot the pattern
Question: 1, 2, 4, 7, 11, ? Which number should replace the question mark in the sequence?
Solution: Look at the difference between consecutive numbers. From 1 to 2 is +1, from 2 to 4 is +2, from 4 to 7 is +3, from 7 to 11 is +4. The differences increase by 1 each time: 1, 2, 3, 4. The next difference must be 5. So, 11 + 5 = 16.
Answer: 16. In number series, your first instinct should always be to check the difference between numbers. If that difference is not constant, look at the pattern of the differences themselves.
2. Numerical analogies: find the relationship
Question: If 6 relates to 3, which number relates to 10 in the exact same way?
Solution: How do you get from 6 to 3? Divide by two (6 ÷ 2 = 3). Apply the exact same rule to 10: 10 ÷ 2 = 5.
Answer: 5. Look for one clear rule in analogy questions. If multiple rules seem to work (such as division and squaring), assume the simplest rule is correct.
3. Verbal analogies: word relationships
Question: If "eye" relates to "seeing," which action relates to "ear"?
Solution: The eye is the organ used for seeing. The ear is the organ used for hearing. The relationship is organ and function.
Answer: Hearing. In verbal analogies, state the relationship between the first pair in a sentence ("the eye enables seeing"), then apply that sentence to the second pair. Questions like this test verbal intelligence. We explained these intelligence components in detail in our article What Is Intelligence?.
4. Find the odd one out
Question: 3, 5, 7, 9, 11 Which of these numbers is different from the rest?
Solution: All of them are odd numbers, so oddness does not differentiate them. Look deeper: 3, 5, 7, and 11 are prime numbers divisible only by 1 and themselves. However, 9 can be written as 3 x 3, which means it is not a prime number.
Answer: 9. For "odd one out" questions, rule out the obvious shared features (like all being odd or even) and look for a underlying sub-rule.
5. Logical deduction: is it definitely true?
Question: If the premises "All roses are flowers" and "Some flowers are red" are true, is the statement "Some roses are red" definitely true?
Solution: Saying all roses are flowers means roses belong inside the group of flowers. However, "some flowers are red" means those red flowers could easily be non-rose flowers. The premises do not guarantee that any of the red flowers are roses.
Answer: No, it is not definitely true. The trap in logic questions is confusing "could be" with "must be." Only accept conclusions that are strictly required by the premises. Rely on the given facts, not your intuition.
6. Matrices: spot the row and column rules
Question: Which number belongs in the last cell of the table below?
2 4 6
3 6 9
4 8 ?
Solution: Each row follows a multiplication pattern. The first row contains multiples of 2 (2, 4, 6), and the second row contains multiples of 3 (3, 6, 9). The third row must contain multiples of 4: 4, 8, and then 12.
Answer: 12. Visual matrix questions (like Raven's Progressive Matrices) use the exact same logic. Look for rules across rows first, then down columns. The combining pattern leads you to the correct choice.
4 helpful tips for solving these questions
- Look for the simplest rule. If a pattern can be explained by both a complex rule and a simple rule, test designers almost always intend the simple one.
- Manage your time. If you get stuck on a question, flag it, skip it, and save it for the end. Missing easy questions costs you far more points than getting stuck on a hard one.
- Build speed on math questions. Fast mental arithmetic saves valuable time. We gathered practical techniques to make this easier in our article Mental Math Techniques for Fast Calculation.
- Do not over-interpret practice scores. Doing well on practice questions does not guarantee the same score on a real test. Read our article Are Online IQ Tests Reliable? to learn more about test accuracy, and check What Is a Good IQ Score? to understand what your score means.
These six types cover the vast majority of questions you will encounter. Now that you understand the logic, try a real assessment: take our free IQ test without registration and see your score right away. If you want more practice, our brain games are perfect for sharpening pattern recognition, logic, and speed every day.