A variable X X\,X is normally distributed. It is given that P(X<52)=0.20P(X<52)=0.20P(X<52)=0.20 and P(X>60)=0.30P(X>60)=0.30P(X>60)=0.30.
Find the mean and standard deviation of XXX.
328 exam-style questions on WJEC A Level Maths 4.2 Statistical distributions (A-level only), covering 4.2.1 Statistical distributions (A-level only), 4.2.2 Statistical distributions (A-level only), and 4.2.3 Statistical distributions (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.