Edexcel A-Level Further Mathematics Further Statistics overview quiz quiz

$E(X^2) - E(X)$

$[E(X)]^2 - E(X^2)$

$E(X^2) - [E(X)]^2$

$E(X) - [E(X)]^2$

$a\operatorname{Var}(X) + b$

$a^2\operatorname{Var}(X) + b$

$a\operatorname{Var}(X)$

$a^2\operatorname{Var}(X)$

Mean $\lambda$, variance $\lambda$

Mean $\lambda$, variance $\lambda^2$

Mean $\lambda^2$, variance $\lambda$

Mean $\frac{1}{\lambda}$, variance $\lambda$

$\lambda^x e^{-x}$

$e^{-\lambda}\frac{\lambda^x}{x!}$

$\binom{n}{x}\lambda^x(1 - \lambda)^{n-x}$

$(1 - \lambda)^{x-1}\lambda$

When $n$ is small and $p$ is large

When $p = 0.5$

When $n$ is large and $p$ is small

When $n = p$

$\sum (O - E)^2 \times E$

$\sum \frac{(O - E)}{E^2}$

$\sum \frac{(O^2 - E^2)}{O}$

$\sum \frac{(O - E)^2}{E}$

$(r - 1)(c - 1)$

$(r - 1) + (c - 1)$

$(r + 1)(c + 1)$

$rc - r - c$

When there are more than 5 degrees of freedom

When there is 1 degree of freedom

Whenever the sample is large

Never in Further Statistics

$p$

$\frac{1 - p}{p^2}$

$\frac{1}{p}$

$\frac{r}{p}$

$\frac{1}{p}$

$rp$

$\frac{r(1 - p)}{p^2}$

$\frac{r}{p}$

Merge them with neighbouring classes

Delete those classes entirely from the table before testing

Double the observed value in each affected class to compensate

Ignore the requirement, as it does not affect the test result