# Tagged Questions

18 views

### Probability of no person being present on a website [on hold]

Given that an average of 2 people are present on a website X at any given minute. What is the probability that no person is present on the website X in a 5 minute interval window (they need to take ...
21 views

### The use of Weighted arithmetic mean to determine the extent to which the data correspond

I don't know when I can ask such question, because it is not a completely mathematic question. I have a text and a topic (single word). I want to check how much this text corresponds to the topic. ...
146 views

### Finding the range from standard deviation and Gaussian Curve

The figure above shows a normal distribution with mean m and standard deviation d, including approximate percents of the distribution corresponding to the six regions shown. Suppose the heights of a ...
31 views

### An organization was surveyed with regard to the number of children each member had…

I am studying for my exam and there is no solution for this question. Can anyone provide the correct answers? Thanks. An organization was surveyed with regard to the number of children each member ...
16 views

59 views

### Define a problem using chernoff bounds

We are preparing this for an exam. Given the division of a plane into a number of regions of different sizes. We would like to find, or guess, which is the biggest region, by doing the following. We ...
274 views

### Mean and Median in a Classic River Crossing Problem

Consider the following classic problem: Four people on the west side of a river wish to use their single boat to get to the east side of a river. Each boat ride can hold at most two people, and the ...
445 views

### Conditional expectation of the product of two independent random variables

Suppose that $a$ and $b$ are independently distributed random variables, with means; $\mu_a$, $\mu_b$ and variances; $\sigma_{a}^2$, $\sigma_b^2$, respectively. Further, let $c=ab + e$, where $e$ is ...
165 views

### Find expectation of conditional random variables

Let $X$ and $Y$ be independent exponential random variables with means 1 and 2 respectively. Let $Z = 2X + Y$. How can I find $E(X|Z)$?
279 views

### Find normal random variable from uniform

Suppose $U$ and $V$ are independent random variables with density $f(u)$ and $g(v)$ respectively. The domain of $U$ is the interval $(0, 1)$ and the domain of $V$ is $v > 0$. After the ...
I'm trying to learn some tricks for how to find joint densities from transformations, but this problem looks really hard. Any help? Suppose the joint density of continuous random variables $X,Y,Z$ is ...