| Exam Board | Edexcel |
|---|---|
| Module | S1 (Statistics 1) |
| Year | 2014 |
| Session | June |
| Marks | 5 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Uniform Distribution |
| Type | Name the distribution |
| Difficulty | Easy -1.8 This is a trivial recall question requiring only basic knowledge of distribution names and fundamental properties. Part (a) asks to name a discrete uniform distribution, parts (b) involve elementary probability calculations (1/10 and 9/10), and part (c) tests basic continuous distribution properties (P(Y=10)=0 for continuous, P(Y<10)=0.5 by symmetry). No problem-solving or calculation beyond direct recall is needed. |
| Spec | 2.04a Discrete probability distributions2.04e Normal distribution: as model N(mu, sigma^2)2.04f Find normal probabilities: Z transformation |
\begin{enumerate}
\item The discrete random variable $X$ has probability distribution
\end{enumerate}
$$\mathrm { P } ( X = x ) = \frac { 1 } { 10 } \quad x = 1,2,3 , \ldots 10$$
(a) Write down the name given to this distribution.\\
(b) Write down the value of\\
(i) $\mathrm { P } ( X = 10 )$\\
(ii) $\mathrm { P } ( X < 10 )$
The continuous random variable $Y$ has the normal distribution $\mathrm { N } \left( 10,2 ^ { 2 } \right)$\\
(c) Write down the value of\\
(i) $\mathrm { P } ( Y = 10 )$\\
(ii) $\mathrm { P } ( Y < 10 )$\\
\hfill \mbox{\textit{Edexcel S1 2014 Q2 [5]}}