Exam-Style Question on ProbabilityA mathematics exam-style question with a worked solution that can be revealed gradually |
Question id: 562. This question is similar to one that appeared on an IB AA Standard paper in 2021. The use of a calculator is not allowed.
A red spinner is designed with five possible outcomes. Let \(X\) be the score obtained when the spinner is spun. The probability distribution for \(X\) is given in the following table.
\(x\) | 3 | 4 | 5 | 8 | 10 |
\(P(X=x)\) | \(p\) | \(2p\) | \(p\) | \(2p\) | \(p\) |
(a) Find the value of p.
(b) Find the value of \(E(x)\).
A blue spinner is also designed with five possible outcomes. Let \(Y\) be the score obtained when the spinner is spun. The probability distribution for \(Y\) is given in the following table.
\(y\) | 1 | 2 | 3 | 4 | 5 |
\(P(Y=y)\) | \(r\) | \(r\) | \(q\) | \(q\) | \(q\) |
(c) State the range of possible values of \(q\).
(d) State the range of possible values of \(r\).
(e) Hence find the range of possible values of \(E(Y)\).
Arnold and Bernie play a game using these spinners. Arnold spins the red spinner once and Bernie spins the blue spinner once. The probability that Arnold's score is less than Bernie's score is \(\frac{1}{7}\).
(f) Find the value of \(E(Y)\).
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
The exam-style questions appearing on this site are based on those set in previous examinations (or sample assessment papers for future examinations) by the major examination boards. The wording, diagrams and figures used in these questions have been changed from the originals so that students can have fresh, relevant problem solving practice even if they have previously worked through the related exam paper.
The solutions to the questions on this website are only available to those who have a Transum Subscription.
Exam-Style Questions Main Page
To search the entire Transum website use the search box in the grey area below.
©1997 - 2024 Transum Mathematics :: For more exam-style questions and worked solutions go to Transum.org/Maths/Exam/