OCR S1 2008 January — Question 4

Exam BoardOCR
ModuleS1 (Statistics 1)
Year2008
SessionJanuary
TopicConditional Probability
TypeGiven conditional, find joint or marginal

4 A supermarket has a large stock of eggs. 40\% of the stock are from a firm called Eggzact. 12\% of the stock are brown eggs from Eggzact. An egg is chosen at random from the stock. Calculate the probability that
  1. this egg is brown, given that it is from Eggzact,
  2. this egg is from Eggzact and is not brown.