Reach for the Star | GCSE Mathematics

L074: Dependent events and assumptions

Objective

Recognise dependence and the assumptions behind a probability model.

Calculator: Non-calculator core; calculator optional only for checking where labelled.

Visual model for Dependent events and assumptions
Points route: Connect 2 · Share 2 · Apply 6 · Review 3 · Stretch 2 · Deep Challenge 3. Record your score honestly after you have checked your answer.

Recall

Retrieve the key fact or method needed for dependent events and assumptions.

Core practice

A bag holds 5 red and 4 blue. Find P(two blue without replacement).

Reasoning

A bag has 4 red and 1 blue. Given the first draw was red, find P(second red without replacement).

Exam-style

Solve an exam-style problem involving dependent events and assumptions. Show working, include a check and interpret your answer.

WWW / EBI

Recall & Review: feedback and extension integration

Lesson L074: Dependent events and assumptions

Objective: Recognise dependence and the assumptions behind a probability model.

60-minute structure: 0-7 Connect & Check; 7-14 Share; 14-25 Present/model; 25-44 Apply route choice/practice; 44-52 independent exam-style check; 52-60 Recall & Review, WWW/EBI and next step.

What Went Well (WWW)

I represented the outcomes systematically, used the correct probability rule and checked that the probabilities or frequencies were consistent.

Even Better If (EBI)

I will show the sample space, branch or set reasoning explicitly, state any dependence or condition and check totals before giving the final probability.

Stretch and deep challenge

Stretch: A bag holds 5 red and 4 blue. Find P(two blue without replacement).

Deep challenge: A bag has 4 red and 1 blue. Given the first draw was red, find P(second red without replacement).