F(x)=2/3x-5 what is the value

Of all the registered automobiles in a city, 12% fail the emissions test. Fourteen automobiles are selected at random to undergo

postnew [5]

Answer:

a) 0.1542

b) 0.7685

c) 0.2315

d) No, it is not unusual

Explanation:

The procedure to make the test meets the requirements of binomial experiments because:

there are two possible mutually exclusive outputs: fail the test, or pass the test.
the probability of each event remains constant during all the test (p=12% = 0.12, for failing the test, and 1-p = 88% = 0.88, for passing the test)
each trial (test) is independent of other trial.

Solution

(a) Find the probability that exactly three of them fail the test.

You want P(X=3)

Using the equation for discrete binomial experiments, the probability of exactly x successes is:

$P(X=x)=C(n,x)\cdot p^x\cdot (1-p)^{(n-x)}$

Substituting C(n,x) with its developed form, that is:

$P(X=x)=\dfrac{n!}{x!\cdot (n-x)!}\cdot p^x\cdot (1-p)^{(n-x)}$

Thus, you must use:

x = 3 (number of automobiles that fail the emissions test)
n = 14 (the number of automobiles selected to undergo the emissions test),
p = 0.12 (probability of failing the test; this is the success of the variable on our binomial experiment)
1 - p = 0.88 (probability of passing the test; this is the fail of the variable on our binomial experiment)

$P(X=3)=\dfrac{14!}{3!\cdot (14-3)!}\cdot 0.12^3\cdot 0.88^{11}=0.1542$

(b) Find the probability that fewer than three of them fail the test.

The probability that fewer than three of them fail the test is the probability that exactly 0, or exactly 1, or exactly 2 fail the test.

That is: P(X=0) + P(X=1) + P(X=2)

Using the same formula:

$P(X=0)=\dfrac{14!}{0!\cdot 14!}\times 0.12^0\cdot 0.88^{14}$

$P(X=0)=0.1670$

$P(X=1)=\dfrac{14!}{1!\cdot 13!}\cdot 0.12^1\cdot 0.88^{13}$

$P(X=1)=0.3188$

$P(X=2)=\dfrac{14!}{2!\cdot 12!}\codt0.12^2\cdot 0.88^{12}$

$P(X=2)=0.2826$

P(X < 3) = P(X = 0) + P(X = 1) + P(X = 2) = 0.7685

(c) Find the probability that more than two of them fail the test.

The probability that more than two of them fail the test is equal to 1 less the probability that exactly 0, or exactly 1, or exactly 2 fail the test:

P( X > 2) = 1 - P( X = 0) - P(X = 1) - P(X = 2)

P X > 2) = 1 - [P(X=0) + P(X = 1) + P(X = 2)]

P (X > 2) = 1 - [0.7685]

P (X > 2) = 0.2315

(d) Would it be unusual for none of them to fail the test?

Remember that not failing the test is the fail of the binomial distribution. Thus, none of them failing the test is the same as all of them passing the test.

You can find the probability that all the automibles pass the emission tests by multiplying the probability of passing the test (0.88) 14 times.

Then, the probability that none of them to fail the test is equal to:

$(1-p)^{14}\\\\(0.88)^{14}=0.1671$

That means that the probability than none of the automobiles of the sample fail the test is 16.71%.

Unusual events are usually taken as events with a probability less than 5%. Thus, this event should not be considered as unusual.

5 0

3 years ago

Can someone please help me solve this?

aleksklad [387]

Answer:

centre = (-5, -4)

radius = 7.42

Step-by-step explanation:

The general form for center-radius is

(x - h)² + (y - k)²= r²

Center = (h, k)

Radius = r

Rearrange the equation.

(x² + 10x) + (y² + 8y) - 14 = 0

Add 14 on both sides.

(x² + 10x) + (y² + 8y) = 14

(10/2)² = 25

(8/2)² = 16

Add 25 and 16 to both sides.

(x² + 10x + 25) + (y² + 8y + 16) = 14 + 25 + 16

Factor left side of the equation.

(x+5)² + (x+4)² = 55

(55) = (7.416198)²

(x+5)² + (x+4)² = 7.42²

The radius is 7.42.

The centre is at (-5, -4).

8 0

3 years ago

Read 2 more answers

C.) Apple offers a buyback program for iPhones after they are 5 years old. They

max2010maxim [7]

Answer: It would not be profitable to sell it back for 100$.

Step-by-step explanation:

It would not be profitable because you might have payed 300-1000$ (Depending what phone you buy) for your phone. It would only be profitable for the older generation of the phones like iPhone 5 and iPhone 6.

4 0

3 years ago

A nutritional consulting company is trying to find what percentage of the population of a town is overweight. The marketing depa

Ymorist [56]

It is undercoverage bias

3 0

3 years ago

Select the values of that are solutions to the inequality x^2+3x-4>0

sergey [27]

Solution:x^2+3x-4=(x+4)(x-1)>0,
therefore, the x range is (-∞,-4)∪(1,+∞).
Answer:(-∞,-4)∪(1,+∞).[

4 0

3 years ago