I don’t know what 12 divided by 6

If Karri takes a 7 question true false test and guess on every question, what is the

dusya [7]

Answer:

The probability that she gets all 7 questions correct is 0.0078.

Step-by-step explanation:

We are given that Karri takes a 7 question true-false test and guess on every question.

The above situation can be represented through binomial distribution;

$P(X = r) = \binom{n}{r} \times p^{r} \times (1-p)^{n-r} ; x = 0,1,2,3,........$

where, n = number of samples (trials) taken = 7 question

r = number of success = all 7 questions correct

p = probability of success which in our question is probability that

question is correct, i.e. p = 50%

Let X = Number of question that are correct

So, X ~ Binom(n = 7, p = 0.50)

Now, the probability that she gets all 7 questions correct is given by = P(X = 7)

P(X = 7) = $\binom{7}{7} \times 0.50^{7} \times (1-0.50)^{7-7}$

= $1 \times 0.50^{7} \times 0.50^{0}$

= 0.0078

6 0

2 years ago

The number of typing errors made by a typist has a Poisson distribution with an average of two errors per page. If more than two

wlad13 [49]

Answer: 0.6767

Step-by-step explanation:

Given : Mean = $\lambda=2$ errors per page

Let X be the number of errors in a particular page.

The formula to calculate the Poisson distribution is given by :_

$P(X=x)=\dfrac{e^{-\lambda}\lambda^x}{x!}$

Now, the probability that a randomly selected page does not need to be retyped is given by :-

$P(X\leq2)=P(0)+P(1)+P(2)\\\\=(\dfrac{e^{-2}2^0}{0!}+\dfrac{e^{-2}2^1}{1!}+\dfrac{e^{-2}2^2}{2!})\\\\=0.135335283237+0.270670566473+0.270670566473\\\\=0.676676416183\approx0.6767$

Hence, the required probability :- 0.6767

6 0

3 years ago

A team of scientists is traveling by boat to study a pod, or group, of dolphins. The equation y = 0.2x can be used to find the d

Alenkinab [10]

Answer:

42 minutes.

Step-by-step explanation:

We know that:

y = 0.2*x

is the equation that that defines the distance, in miles, that the boat travels in x minutes.

We know that the dolphins are at 8.4 miles from the boat.

Then when we have y = 8.4, this will mean that the boat reached the dolphins.

Then we need to solve the equation:

y = 8.4 = 0.2*x

for x

To do that, we just need to isolate x in one side of the equation, so we can just divide both sides by 0.2 to get:

8.4/0.2 = (0.2*x)/0.2

42 = x

And x is time in minutes, thus, the boat needs to travel for 42 minutes to reach the dolphins.

6 0

2 years ago

Find fourth proportional of 6, 9, 18. Please say me correct answer

olganol [36]

A: 3

Good luck on everything

4 0

2 years ago

Danielle earns a 8.25% commission on everything she sells at the electronics store where she works. She also earns a base salary

Mariulka [41]

Answer: her sales last week was $4300.

Step-by-step explanation:

Let x represent her her sales in a week.

Danielle earns a 8.25% commission on everything she sells at the electronics store where she works. This means that the commission she gets if she makes sales of $x is 0.0825x

She also earns a base salary of $675 per week. The expression for the total earnings for a week in which she made sales of $x would be

0.0825x + 675

if her total earnings for last week were $1,029.75, it means that

0.0825x + 675 = 1029.75

0.0825x = 1029.75 - 675

0.0825x = 354.75

x = 354.75/0.0825

x = $4300

3 0

2 years ago