Prove that the expectation of the number of black balls preceding the first white ball is $\frac {b}{w+1}$
73958
Expected value in an urn problem
20750
Proving an equality regarding fully independent events
152686
How to derive $E=mc^{2}$?
77754
Given that $X \sim \operatorname{Binomial}(n,p)$, Find $\mathbb{E}[X(X-1)(X-2)(X-3)]$
129170
Deriving the expectation of $[\hat X,\hat H]$
95415
proof relating to limit definition of e
114603
Conditional Expectation of Composite Function
114026
Expectation and variance of the geometric distribution
71743
$\lim (1+\frac{1}{n+1})^n = e$
99435
Proof of the inclusion-exclusion formula in probability
64856
Finding $E(X\mid X>Y)$ when $X,Y$ are i.i.d $U(0,1)$
86635
Optimizing $(X_{n}+c)^{2}$ to show that $P(\overline{X}_{n}\geq \lambda) \leq E(X_{n}^{2})/(EX_{n}^{2}+ \lambda^{2})$
89544
Expectation of a random variable that takes points in the natural numbers
67489
How to show that $E[(\hat\theta -\theta)^2]<Var(\bar X)=\dfrac{1}{n}$?
72735
Understanding the proof of a formula for $p^e\Vert n!$
38785
Prove previsibility and $E[X_{T \wedge n}] \le E[X_{S \wedge n}]$
95022
Help understanding proof of the following statement $E(Y) = \sum_{i = 1}^{\infty} P(Y \geq k)$