Can somebody tell me how to do this?

Based on past experience, the main printer in a university computer centre is operating properly 90% of the time. Suppose inspec

yaroslaw [1]

Answer:

a) 38.74% probability that the main printer is operating properly for exactly 9 inspections.

b) Approximately 100% probability that the main printer is operating properly for at least 3 inspections.

c) The expected number of inspections in which the main printer is operating properly is 9.

Step-by-step explanation:

For each inspection, there are only two possible outcomes. Either it is operating correctly, or it is not. The probability of the printer operating correctly for an inspection is independent of any other inspection, which means that the binomial probability distribution is used to solve this question.

Binomial probability distribution

The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

In which $C_{n,x}$ is the number of different combinations of x objects from a set of n elements, given by the following formula.

$C_{n,x} = \frac{n!}{x!(n-x)!}$

And p is the probability of X happening.

Based on past experience, the main printer in a university computer centre is operating properly 90% of the time.

This means that $p = 0.9$

Suppose inspections are made at 10 randomly selected times.

This means that $n = 10$

A) What is the probability that the main printer is operating properly for exactly 9 inspections.

This is $P(X = 9)$ . So

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

$P(X = 9) = C_{10,9}.(0.9)^{9}.(0.1)^{1} = 0.3874$

38.74% probability that the main printer is operating properly for exactly 9 inspections.

B) What is the probability that the main printer is operating properly for at least 3 inspections?

This is:

$P(X \geq 3) = 1 - P(X < 3)$

In which

$P(X < 3) = P(X = 0) + P(X = 1) + P(X = 2)$

So

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

$P(X = 0) = C_{10,0}.(0.9)^{0}.(0.1)^{10} \approx 0$

$P(X = 1) = C_{10,1}.(0.9)^{1}.(0.1)^{9} \approx 0$

$P(X = 2) = C_{10,2}.(0.9)^{2}.(0.1)^{8} \approx 0$

Thus:

$P(X < 3) = P(X = 0) + P(X = 1) + P(X = 2) = 0 + 0 + 0 = 0$

Then:

$P(X \geq 3) = 1 - P(X < 3) = 1 - 0 = 1$

Approximately 100% probability that the main printer is operating properly for at least 3 inspections.

C) What is the expected number of inspections in which the main printer is operating properly?

The expected value for the binomial distribution is given by:

$E(X) = np$

In this question:

$E(X) = 10(0.9) = 9$

3 0

3 years ago

Walter Peyton’s NFL career lasted 13 seasons and he averaged 295 rushing yards per season. Use a strategy to determine how many

padilas [110]

Answer: 3835 Yards

Step-by-step explanation:

This is a simple problem

First, take 295 and multiply by 13

like so: 295x13

This will result in

3835 yards

7 0

2 years ago

Find the area of the figure, in square meters, to 1 decimal place.

alukav5142 [94]

Answer:

Where is the picture of the figure

Step-by-step explanation:

6 0

2 years ago

3.478 / 37 = ____ can someone explain how to do it I don't understand long division :,)

DiKsa [7]

Answer:

.094

Step-by-step explanation:

Long division is really annoying, so here we go. Have it written on your paper and follow along.

When doing long division, you want to ignore the decimal until the very end. So how many times does 37 fit into 34? It doesn't, so write a 0 on top. Instead ask how many times it can fit into 347. It can only fit 9 times, so write the 9 next to the 0. Now multiply 37 times 9, since it can fit in 9 times. Place that number (333) under the 347. Subtract that and write the new number underneath (14). Bring down the 8 and add it to the end of your new number (now 148). How many times does 37 fit into 148? It goes in 4 times perfectly. Write the 4 on top, and now multiply 4 times 37, since it goes in 4 times. Put that number (148) below the original 148, subtract, and they cancel out. You're done with the problem! Add the decimal back in. Since there 3 numbers after the decimal in 3.478, the decimal will go before 3 numbers in your answer. Hope this helped!

5 0

3 years ago

3x-8 i nedd help finding what x represent

seropon [69]

8/3

divide both sides by 3 and you get x=8/3

7 0

3 years ago