Context for 19(a)A bag contains some coloured counters. The probability of picking a red counter from the bag is 0.24 .
19(a)(i)Probability Tree Diagrams Conditional ProbabilityEasy1 markFind the probability of not picking a red counter from the bag.AnswerGrade answerSolutionGrading criteria
19(a)(ii)Probability Tree Diagrams Conditional ProbabilityEasy2 marksSunil picks a counter at random from the bag and then replaces it. He then picks a second counter at random from the bag.Work out the probability that only one of the counters is red.AnswerGrade answerSolutionGrading criteria
19(b)Probability Tree Diagrams Conditional ProbabilityMedium3 marksA box contains 50 pens. There are n blue pens in the box.Ahmed picks two of the pens from the box at random without replacement. The probability that both pens are blue is 353.Find the value of n.WorkingTypeWriteMath0 wordsn=Grade answerSolutionGrading criteria