Statistics and Probability Answers

ther are 15 items in a bag. in which 11 are good and 4 are defective . if two items are selected one by one '
1- with replacement.
2- Without replacement'
find the probability that first item is defective and second is good

[img]https://upload.cc/i1/2020/05/09/FXpIjM.jpg[/img]


whole question is in picture,please answer the whole question,B=4,you can sub B=4 in b part

find the mean and standard deviation of a random variable with pdf f(x)=e^-x ,x>=0

It is known that 10% of bolts manufactured by a factory are defective. If a random sample of 100 bolts is chosen at random from a day's production, construct the sampling distribution of (1) the number of defective bolts, (2) the proportion of defective bolts.

The lifetime of a machine is continuous on the interval (0; 40) with probability density
function f, where f(t) is proportional to (t + 10)−2, and t is the lifetime in years.
Calculate the probability that the lifetime of the machine part is less than 10 years.
Hint: Show that f(t) is legitimate and find the proportionality constant.

Suppose X follows the uniform distribution from the range (-a,a) where a is greater than zero. Find the value of a such that P(X<1)=(1/3)=P(X>1)

Write an proper report on poverty in Pakistan and also consider the pandemic situation in Pakistan?

The lifetime of a machine is continuous on the interval (0 ,40) with probability density function f,where f(t) is proportional to (t+10)^-2 and t is the lifetime in years.Calculate the probability that the lifetime of the machine part is less than 10 years

Let X be a continuous r.v with density function
f(x) = ( |x|
10
, for r 2 < x < 4 0, elsewhere
. Calculate the expected value of X.

The measurement instruments used in the tool room of a company are found [2] to have failure rate of 0.02 per year. What does this mean? What is the
relationship between Reliability and Failure rate?