Rakesh went up to take an exam. After the exam, while explaining the structure of the paper, the teacher said:40%of the total questions were difficult and 20% of
those were on algebra and 30% of those were on geometry. Also 10% and 20% of
easy qns were on algebra and geometry. All the qns that Rakesh attempted were
either on algebra or on geometry. What is the probability that Rakesh found all
the qns difficult? (qns are either easy or difficult).... answer given is 14/27.......