| Exam Board | CAIE |
|---|---|
| Module | S2 (Statistics 2) |
| Year | 2021 |
| Session | November |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Central limit theorem |
1 It is known that the height $H$, in metres, of trees of a certain kind has the distribution $\mathrm { N } ( 12.5,10.24 )$. A scientist takes a random sample of 25 trees of this kind and finds the sample mean, $\bar { H }$, of the heights.\\
(a) State the distribution of $\bar { H }$, giving the values of any parameters.\\
(b) Find $\mathrm { P } ( 12 < \bar { H } < 13 )$.\\
\hfill \mbox{\textit{CAIE S2 2021 Q1}}