IB command term
Deduce in IB exams: what the command term asks of you
By Michael Thompson - Head of Teaching Excellence; 15 years as an IB Coordinator
Deduce asks you to reach a conclusion that follows from the information you have been given. The answer is already contained in the question, so you are marked on the visible chain of reasoning that extracts it.
Paraphrased from the command-term definitions in the IB Diploma Programme subject guides (International Baccalaureate Organization).
At a glance
Data, working and diagrams
Answer shape: Visible working, read data or a labelled diagram
What deduce asks you to do
When a question says deduce, you reach a conclusion that follows from the information you have been given. You are not being asked to recall a fact or to invent something new. The answer is already contained in the material in front of you, and your job is to draw it out in a logical way.
Show the chain of reasoning
What you are marked on is the chain of reasoning that extracts the answer. A bare conclusion without visible logic can miss marks even when it is correct. Write each step, and use linking words such as because, therefore and which means, so that a reader can check every move you make from the given information to your conclusion.
Stay inside the given information
Work only from what the question gives you plus established theory. If you bring in outside facts that the question did not supply, deduction turns into guesswork. Before you write, ask yourself which piece of the given information supports each statement you are about to make.
Write down intermediate results
Many deductions pass through an intermediate result on the way to the final answer. Write that result down. Correct method earns credit, so a visible middle step protects you if a later step goes wrong, and it makes your reasoning easier to follow.
Where it appears
Chemistry
In chemistry, deduce means drawing a conclusion from the data or information in the question together with established chemical theory. State each step and any intermediate result.
Chemistry tutoringMathematics AA
In mathematics AA, deduce means a conclusion that follows from what the question gives you. Write the logical steps and any intermediate result, because method is credited, not only the final line.
Mathematics AA tutoringPhysics
In physics, deduce means reasoning from the information supplied plus established theory. Link each statement with because or therefore, and record intermediate results so the chain can be checked.
Physics tutoringBiology
In biology, deduce means reaching a conclusion that follows from the information given, such as data or a description. Do not add outside facts; show which given detail supports each step.
Biology tutoringCommon mistakes
- Writing only the final conclusion with no visible logic, even when it is correct.
- Importing outside facts that the question did not give, so the answer becomes a guess.
- Leaving out an intermediate result that your method passes through.
- Skipping linking words, so the reader cannot tell why one step follows from the previous one.
- Treating deduce as a recall question instead of working from the information in front of you.
Frequently asked questions
- What does deduce mean in IB exams?
- It means reaching a conclusion that follows from the information you have been given. The answer is contained in the question, and you show the reasoning that extracts it.
- Is a correct answer enough when the question says deduce?
- Not necessarily. A bare conclusion without visible logic can miss marks even when it is right, so write out the steps that lead you to it.
- Can I use facts that are not in the question?
- Work only from the given information plus established theory. Bringing in outside facts turns deduction into guesswork and weakens the chain of reasoning.
- How is deduce different from determine, predict and interpret?
- These terms are often confused with deduce. Each has its own page in this resource, so read them side by side and check the wording of the specific question you face.
Related command terms
Keep going
Want someone to check your answers against these command terms? We match you with an expert IB tutor within 24 hours.
Get matched with a tutor