Calculating Expected Frequency
This deep dive covers Calculating Expected Frequency within Expected Frequency for GCSE Mathematics. Revise Expected Frequency in Probability for GCSE Mathematics with 14 exam-style questions and 12 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 3 of 5 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 3 of 5
Practice
14 questions
Recall
12 flashcards
Calculating Expected Frequency
Formula
Expected Frequency = Probability × Number of trials
Example 1: Coin Flipping
If you flip a coin 200 times, how many heads do you expect?
Expected heads = P(heads) × Number of flips = 0.5 × 200 = 100
Example 2: Quality Control
A factory knows that 3% of its products are defective. In a batch of 500 items, how many defects are expected?
Expected defects = P(defective) × Number of items = 0.03 × 500 = 15
Using Experimental Probability
A basketball player has made 15 out of 25 free throws in practice. If they take 40 free throws in a game, how many do we expect them to make?
Experimental probability = 15/25 = 0.6
Expected makes = 0.6 × 40 = 24
Keep building this topic
Read this section alongside the surrounding pages in Expected Frequency. That gives you the full topic sequence instead of a single isolated revision point.
Practice Questions for Expected Frequency
Which formula correctly gives the expected frequency of an event?
A fair coin is flipped 50 times. The expected number of heads is 25. In the actual experiment, only 18 heads are recorded. Explain why the actual number of heads may differ from the expected number of heads.
Quick Recall Flashcards
14 questions on Expected Frequency — practise free
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