IB skill practice

Calculate probability with diagrams

Calculate probability from sample spaces and simple diagrams with exact fractions.

Paper 1 5 marks Difficulty 1

Use the complement rule

In a practice set, the probability of answering a question incorrectly is \(\frac{3}{10}\). Find the probability of answering it correctly.

Worked practice: probability

Write the probability as a fraction or decimal, then interpret it if the question asks for a conclusion.