Ask question

Ask question

All categories

2 years ago

5

A local pizza restaurant delivery time has a uniform distribution over 0 to 60 minutes. What is the probability that the pizza d

elivery time is more than 30 minutes on a given day? Answer: (Round to 2 decimal place.)

1 answer:

Likurg_2 [28]2 years ago

7 0

Answer:

$X \sim Unif (a= 0, b=60)$

And we want to find the following probability:

$P(X>30)$

And for this case we can use the cumulative distribution given by:

$F(x) =\frac{x-a}{b-a}, a \leq x \leq b$

And for this case if we use this formula and the complement rule we have:

$P(X>30)= 1-P(X$

Step-by-step explanation:

Let X the random variable who represent the pizza delivery time and we know that the distribution for x is given by:

$X \sim Unif (a= 0, b=60)$

And we want to find the following probability:

$P(X>30)$

And for this case we can use the cumulative distribution given by:

$F(x) =\frac{x-a}{b-a}, a \leq x \leq b$

And for this case if we use this formula and the complement rule we have:

$P(X>30)= 1-P(X$

You might be interested in

A helicopter flies 8 km due north from A to B. It then flies 5 km from B to C and returns to A as shown in the figure. Angle ABC

In-s [12.5K]

Please consider the attached graph.

We have been given that a helicopter flies 8 km due north from A to B. It then flies 5 km from B to C and returns to A as shown in the figure. The measure of angle ABC is 150°. We are asked to find the area of triangle ABC.

We will use trigonometric area formula to solve our given problem.

$A=\frac{1}{2}a\cdot c\cdot\text{sin}(b)$ , where angle b is angle between sides a and c.

For our given triangle $a=5,c=8$ and measure of angle b is 150 degrees.

$A=\frac{1}{2}(5)\cdot (8)\cdot\text{sin}(150^{\circ})$

$A=5\cdot 4\cdot(0.5)$

$A=10$

Therefore, the area of the triangle ABC is 10 square kilo-meters and option 'c' is the correct choice.

6 0

2 years ago

Pls help i have a test tmrw and i don't understand anything

Alex777 [14]

Answer:

Step-by-step explanation:

Go on super teacher worksheets to get the answer key

3 0

2 years ago

James is four years younger than Austin. If three times James' age is increased by the square of Austin's age, the result is 28.

lara31 [8.8K]

Let's use J for James's age and A for Austin's age. The equations are:

J = A - 4
3J + A² = 28

Just plug (A - 4) in the place of J in the second equation. This gives you:

3(A - 4) + A² = 28
-->
A² + 3A - 12 = 28
-->
A² + 3A - 40 = 0
-->
(A - 5)(A + 8) = 0
-->
A = 5 or -8

-8 is nonsense, so Austin is 5 years old. Therefore, James is 1 year old.

7 0

2 years ago

A website advertises job openings on its website, but job seekers have to pay to access the list of job openings. The website re

nataly862011 [7]

Answer:

The 90% confidence interval would be given by (57.006;62.994)

Step-by-step explanation:

Previous concepts

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

$\bar X=60$ represent the sample mean

$\mu$ population mean (variable of interest)

$\sigma=10$ represent the population standard deviation

n=30 represent the sample size

Assuming the X follows a normal distribution

$X \sim N(\mu, \sigma=10)$

The sample mean $\bar X$ is distributed on this way:

$\bar X \sim N(\mu, \frac{\sigma}{\sqrt{n}})$

The confidence interval on this case is given by:

$\bar X \pm z_{\alpha/2}\frac{\sigma}{\sqrt{n}}$ (1)

The next step would be find the value of $\z_{\alpha/2}$ , $\alpha=1-0.90=0.1$ , $\alpha/2 =0.05$ and $z_\alpha/2=1.64$

Using the normal standard table, excel or a calculator we see that:

$z_{\alpha/2}=1.64$

Since we have all the values we can replace:

$60 - 1.64\frac{10}{\sqrt{30}}=57.006$

$60 + 1.64\frac{10}{\sqrt{30}}=62.994$

So on this case the 90% confidence interval would be given by (57.006;62.994)

5 0

2 years ago

Students at a high school were asked about their favorite outdoor activity. The results are shown in the two-way frequency table

ruslelena [56]

Answer:

More girls chose canoeing as their favorite outdoor activity than those who chose skiing.

More boys chose skiing as their favorite outdoor activity than girls.

There were more boys surveyed than girls.

More students chose camping as their favorite outdoor activity than the combined number of students who chose canoeing or skiing.

Step-by-step explanation:

The last answer:-

Number choosing camping = 81 and the number choosing canoeing or fishing = 35 + 45 = 80.

8 0

2 years ago

Read 2 more answers