2022 MI P2 Q7
A bag contains three red balls, $n-1$ blue balls and $n$ white ball, where $n\ge 3$. The balls are identical except for their colour. Two balls are drawn at random, without replacement. Two points is given for each red ball drawn, one point is given for each blue ball drawn and one point is deducted for each white ball drawn. Let $X$ be the score obtained from adding the points of the two balls.
(i)
Show that $\text{P}\left( X=0 \right)=\frac{n\left( n-1 \right)}{\left( n+1 \right)\left( 2n+1 \right)}$.
[2]
(ii)
Find the probability distribution of $X$.
[3]
(iii)
Given that the average score of picking the two balls is at least $0.16$, find the largest possible number of white balls in the bag.
[3]
Suggested Video Solutions
Our H2 Math Tuition includes
- Question Bank with Video solutions to 1400+ questions
- Online Portal
- H2 Math Summary Notes
- Structured Curriculum and Notes
Share with your friends!
Continue reading
Maximizing June Holidays: Is Joining a Crash Course Necessary?
As June holidays approach, students find themselves at a crucial juncture in their academic journey. With the semester winding down and exams looming on the horizon, the pressure to excel
5 Exam Preparation Tips: How We Help Students Excel in Exams
In the ever-evolving landscape of education, where academic success is often measured by performance in exams, the need for effective test preparation has never been more critical. Students face a
List MF 27
What is the MF 27? The MF 27, set to replace the MF 26 from 2025, is a comprehensive formula sheet developed by the Ministry of Education Singapore in collaboration