Which of the following represent the number of units

Simplify (4-3i)(5+2i)

Anna [14]

Hey I'm probably too late but your answer would be 26-7i

Hope this helps :)

8 0

3 years ago

Write the ordered pair that describes a point 12 units down from and 7 units to the right of the origin.

emmainna [20.7K]

(-7,-12) s it both down and to the right of the origin

8 0

3 years ago

Read 2 more answers

Assume that during each second, a job arrives at a webserver with probability 0.03. Use the Poisson distribution to estimate the

Savatey [412]

Answer:

The probability that at lest one job will be missed in 57 second is $=1- e^{-1.71}$ =0.819134

Step-by-step explanation:

Poisson distribution:

A discrete random variable X having the enumerable set {0,1,2,....} as the spectrum, is said to be Poisson distribution.

$P(X=x)=\frac{e^{-\lambda t}({-\lambda t})^x}{x!}$ for x=0,1,2...

λ is the average per unit time

Given that, a job arrives at a web server with the probability 0.03.

Here λ=0.03, t=57 second.

The probability that at lest one job will be missed in 57 second is

=P(X≥1)

=1- P(X<1)

=1- P(X=0)

$=1-\frac{e^{-1.71}(1.71)^0}{0!}$

$=1- e^{-1.71}$

=0.819134

6 0

4 years ago

An article written for a magazine claims that 78% of the magazine's subscribers report eating healthily the previous day. Suppos

Schach [20]

Answer:

89.44% probability that less than 80% of the sample would report eating healthily the previous day

Step-by-step explanation:

We use the binomial approximation to the normal to solve this question.

Binomial probability distribution

Probability of exactly x sucesses on n repeated trials, with p probability.

Can be approximated to a normal distribution, using the expected value and the standard deviation.

The expected value of the binomial distribution is:

$E(X) = np$

The standard deviation of the binomial distribution is:

$\sqrt{V(X)} = \sqrt{np(1-p)}$

Normal probability distribution

Problems of normally distributed samples can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

When we are approximating a binomial distribution to a normal one, we have that $\mu = E(X)$ , $\sigma = \sqrt{V(X)}$ .