A botanical researcher is studying a large population of orchids. In this population, 15%15\%15% of the orchids exhibit the rare "Purple" phenotype (PPP) and the remaining 85%85\%85% exhibit the standard "White" phenotype (WWW). The researcher selects two orchids at random from this population for genetic testing.
Calculate the probability that both selected orchids exhibit the same phenotype.
Determine the probability that both orchids are Purple, given that at least one of the orchids is found to be Purple.
Practise Edexcel A Level Maths Conditional Probability with exam-style questions for A Level Maths. 100 questions covering Set Notation, Conditional Probability, Conditional Probabilities in Venn Diagrams, Probability Formulae, and Tree Diagrams, matched to the Edexcel A Level Maths (9MA0) specification and written in Paper 1, Paper 2 and Paper 3 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.