58 results.
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Question in Content created by Newcastle University
Normal distribution $X \sim N(\mu,\sigma^2)$ given. Find $P(a \lt X \lt b)$. Find expectation, variance, $P(c \lt \overline{X} \lt d)$ for sample mean $\overline{X}$.
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Question in Content created by Newcastle University
Converting odds to probabilities.
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Question in Content created by Newcastle University
Given three linear combinations of four i.i.d. variables, find the expectation and variance of these estimators of the mean $\mu$. Which are unbiased and efficient?
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Question in Content created by Newcastle University
Given 32 datapoints in a table find their minimum, lower quartile, median, upper quartile, and maximum.
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Question in Content created by Newcastle University
$A,\;B$ $2 \times 2$ matrices. Find eigenvalues and eigenvectors of both. Hence or otherwise, find $B^n$ for largish $n$.
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Question in Content created by Newcastle University
$x_n=\frac{an+b}{cn+d}$. Find the least integer $N$ such that $\left|x_n -\frac{a}{c}\right| \le 10 ^{-r},\;n\geq N$, $2\leq r \leq 6$.
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Question in Content created by Newcastle University
Let $x_n=\frac{an+b}{cn+d},\;\;n=1,\;2\ldots$. Find $\lim_{x \to\infty} x_n=L$ and find least $N$ such that $|x_n-L| \le 10^{-r},\;n \geq N,\;r \in \{2,\;3,\;4\}$.
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Question in Content created by Newcastle University
Find (hyperbolic substitution):
$\displaystyle \int_{b}^{2b} \left(\frac{1}{\sqrt{a^2x^2-b^2}}\right)\;dx$ -
Question in Content created by Newcastle University
An experiment is performed twice, each with $5$ outcomes
$x_i,\;y_i,\;i=1,\dots 5$ . Find mean and s.d. of their differences $y_i-x_i,\;i=1,\dots 5$.
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Question in Content created by Newcastle University
Determine if the following describes a probability mass function.
$P(X=x) = \frac{ax+b}{c},\;\;x \in S=\{n_1,\;n_2,\;n_3,\;n_4\}\subset \mathbb{R}$.
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Question in Content created by Newcastle University
Given subset $T \subset S$ of $m$ objects in $n$ find the probability of choosing without replacement $r\lt n-m$ from $S$ and not choosing any element in $T$.
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Question in Content created by Newcastle University
$X \sim \operatorname{Binomial}(n,p)$. Find $P(X=a)$, $P(X \leq b)$, $E[X],\;\operatorname{Var}(X)$.
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Question in Content created by Newcastle University
$W \sim \operatorname{Geometric}(p)$. Find $P(W=a)$, $P(b \le W \le c)$, $E[W]$, $\operatorname{Var}(W)$.
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Question in Content created by Newcastle University
$Y \sim \operatorname{Poisson}(p)$. Find $P(Y=a)$, $P(Y \gt b)$, $E[Y],\;\operatorname{Var}(Y)$.
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Question in Content created by Newcastle University
Differentiate the following functions: $\displaystyle x ^ n \sinh(ax + b),\;\tanh(cx+d),\;\ln(\cosh(px+q))$
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Question in Content created by Newcastle University
Eight questions on finding least upper bounds and greatest lower bounds of various sets.
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Question in Content created by Newcastle University
Modular arithmetic. Find the following numbers modulo the given number $n$. Three examples to do.
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Question in Probability
r digits are picked at random (with replacement) from the set $\{0,\;1,\;2,\ldots,\;n\}$. Probabilities that 1) all $\lt k$, 2) largest is $k$?
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Question in Christian's workspace
Find the determinant and inverse of three $2 \times 2$ invertible matrices.
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Question in Ricardo's workspace
The random variable $X$ has a PDF which involves a parameter $c$. Find the value of $c$. Find the distribution function $F_X(x)$ and $P(a \lt X \lt b)$.
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Question in Bill's workspace
Given the pdf $f(x)=\frac{a-bx}{c},\;r \leq x \leq s,\;f(x)=0$ else, find $P(X \gt p)$, $P(X \gt q | X \gt t)$.
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Question in Bill's workspace
Given a probability mass function $P(X=i)$ with outcomes $i \in \{0,1,2,\ldots 8\}$, find the expectation $E$ and $P(X \gt E)$.
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Question in Bill's workspace
The random variable $X$ has a PDF which involves a parameter $c$. Find the value of $c$. Find the distribution function $F_X(x)$ and $P(a \lt X \lt b)$.
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Question in Bill's workspace
Two numbers from a set of $5$ numbers are chosen at random, without replacement. Find the distribution $X$ of their sum and $E[X]$.
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Question in Bill's workspace
Determine if the following describes a probability mass function.
$P(X=x) = \frac{ax+b}{c},\;\;x \in S=\{n_1,\;n_2,\;n_3,\;n_4\}\subset \mathbb{R}$.
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Question in Bill's workspace
Find the critical point $(0,a)$ of the function: $f(x,y)=ax^3+bx^2y+cy^2+dy+f$ and find its type using the test given by the Hessian matrix.
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Question in Michael's workspace
Find the determinant and inverse of three $2 \times 2$ invertible matrices.
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Question in Christoph's workspace
Find the determinant and inverse of three $2 \times 2$ invertible matrices.