80 people were asked which social media apps they use: Instagram, TikTok, and Snapchat. 20 people use all three apps. 50 people use Instagram. 10 people use Instagram and TikTok but not Snapchat. 35 people use TikTok and Snapchat. 2 people do not use any of these apps. All 45 people who use Snapchat use at least one other app.
Two of the 80 people are chosen at random. Work out the probability that they both use TikTok.
Practise Edexcel GCSE Maths Conditional Probability with exam-style questions for Foundation and Higher tier. 28 questions, matched to the Edexcel GCSE Maths (1MA1) 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.