Exam-Style Question on Probability Distribution
A mathematics exam-style question with a worked solution that can be revealed gradually
Question id: 430. This question is similar to one that appeared on an IB AA Standard paper in 2019. The use of a calculator is allowed.
Amelia selects a disc from a bag containing 5 green discs, 4 blue discs and 3 red discs.
She wins £1 for a green disc, £3 for a blue disc, and £7 for a red disk. The game costs £4 to play.
(a) Calculate the expected gain for this game, and hence show that the game is not fair.
After a while, \(n\) red discs are added and Amelia wins £5 if she selects one. The game is now fair.
(b) Create an equation to represent this information.
(c) Hence, calculate the value of \(n\).
The worked solutions to these exam-style questions are only available to those who have a Transum Subscription.
Subscribers can drag down the panel to reveal the solution line by line. This is a very helpful strategy for the student who does not know how to do the question but given a clue, a peep at the beginnings of a method, they may be able to make progress themselves.
This could be a great resource for a teacher using a projector or for a parent helping their child work through the solution to this question. The worked solutions also contain screen shots (where needed) of the step by step calculator procedures.
A subscription also opens up the answers to all of the other online exercises, puzzles and lesson starters on Transum Mathematics and provides an ad-free browsing experience.
Drag this panel down to reveal the solution
©1997 - 2020 Transum Mathematics :: For more exam-style questions and worked solutions go to Transum.org/Maths/Exam/