CAIE S1 2008 June — Question 7

Exam BoardCAIE
ModuleS1 (Statistics 1)
Year2008
SessionJune
TopicBinomial Distribution
TypeNormal approximation to binomial

7 A die is biased so that the probability of throwing a 5 is 0.75 and the probabilities of throwing a 1,2 , 3 , 4 or 6 are all equal.
  1. The die is thrown three times. Find the probability that the result is a 1 followed by a 5 followed by any even number.
  2. Find the probability that, out of 10 throws of this die, at least 8 throws result in a 5 .
  3. The die is thrown 90 times. Using an appropriate approximation, find the probability that a 5 is thrown more than 60 times.