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2 years ago

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A researcher wishes her patients to try a new medicine for depression. How many different ways can she select 5 patients from 50

patients?

1 answer:

Readme [11.4K]2 years ago

7 0

Answer:

she can select 10 different ways

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A recipe calls for 1 part beans to 1½ parts rice. if 1½ parts of beans are used, how much rice should be used?

riadik2000 [5.3K]

$1 \text{ part beans} \longrightarrow 1\dfrac{1}{2} \text{ parts rice}$

$1 \dfrac{1}{2} \text{ part beans} \longrightarrow 1\dfrac{1}{2} \times 1 \dfrac{1}{2} \text{ parts rice}$

$1 \dfrac{1}{2} \text{ part beans} \longrightarrow \dfrac{3}{2} \times \dfrac{3}{2} \text{ parts rice}$

$1 \dfrac{1}{2} \text{ part beans} \longrightarrow \dfrac{9}{4} \text{ parts rice}$

$1 \dfrac{1}{2} \text{ part beans} \longrightarrow 2\dfrac{1}{4} \text{ parts rice}$

8 0

2 years ago

Many us employess received a 3% raise in 2012 suppose an employee made 47,000 in 2011 and received a 3% raise. What did she make

WITCHER [35]

First lets get 3% into decimal form.

3% is 3/100 = 0.03

Now multiply 0.03 by 47000 to get how much extra money she was going to get.

47000 * 0.03 = 1410

Now we just add
47000 + 1410 = 48410 is what she was going to make in 2012

Another way to do this is

(47000)(1+0.03) = 48410

you would use (1+0.03) which tells you she increased in pay.

4 0

2 years ago

A website manager has noticed that during the evening hours, about 3.23.2 people per minute check out from their shopping cart

aleksandrvk [35]

Answer:

1. c. Poisson

2. 0.9592 = 95.92% probability that in any one minute at least one purchase is made.

3. 0.0017 = 0.17% probability that no one makes a purchase in the next 2 minutes.

Step-by-step explanation:

We have only the mean, which means that the Poisson distribution is used to solve this question, and thus the answer to question 1 is given by option c.

Poisson distribution:

In a Poisson distribution, the probability that X represents the number of successes of a random variable is given by the following formula:

$P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}$

In which

x is the number of sucesses

e = 2.71828 is the Euler number

$\mu$ is the mean in the given interval.

Mean of 3.2 minutes:

This means that $\mu = 3.2n$ , in which n is the number of minutes.

2. What is the probability that in any one minute at least one purchase is made?

$n = 1$ , so $\mu = 3.2$ .

This probability is:

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

In which

$P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}$

$P(X = 0) = \frac{e^{-3.2}*3.2^{0}}{(0)!} = 0.0408$

So

$P(X \geq 1) = 1 - P(X = 0) = 1 - 0.0408 = 0.9592$

0.9592 = 95.92% probability that in any one minute at least one purchase is made.

3. What is the probability that no one makes a purchase in the next 2 minutes?

2 minutes, so $n = 2, \mu = 3.2(2) = 6.4$

This probability is P(X = 0). So

$P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}$

$P(X = 0) = \frac{e^{-6.4}*6.4^{0}}{(0)!} = 0.0017$

0.0017 = 0.17% probability that no one makes a purchase in the next 2 minutes.

7 0

2 years ago

Jamie recently started working as

Mumz [18]

Answer:

B

Step-by-step explanation:

From annual salary of 42,600, we have to subtract the following percentages:

<u>Social Security:</u>

0.062 * 42,600 = 2641.2

<u>Medicare:</u>

0.014 * 42,600 = 596.4

<u>State Income Tax:</u>

0.03 * 42,600 = 1278

<u>Federal Income Tax:</u>

0.13 * 42,600 = 5538

<u>Total Deductions</u> (from percentages) = 2641.2 + 596.4 + 1278 + 5538 = 10053.6

Now, remaining salary:

42,600 - 10053.6 = 32546.4 (annual)

Divided by 12 to get monthly:

32546.4 / 12 = 2712.2 (monthly)

Now, monthly deductions are:

260 + 280 = 540

<u>Net Salary:</u> 2712.2 - 540 =2172.2

5 0

2 years ago

a rectangular lawn has an area of a^3 - 125. use the difference of cubes to find out the dimensions of the rectangle.

ANEK [815]

The area of a rectangle is the product of its dimensions

The dimensions of the rectangle are: $\mathbf{Length = a -5}$ and $\mathbf{Width = a^2 + 5a + 25}$

The area is given as:

$\mathbf{Area = a^3 - 125}$

Express 125 as 5^3

$\mathbf{Area = a^3 - 5^3}$

Apply difference of cubes

$\mathbf{Area = (a - 5)(a^2 + 5a + 5^2)}$

$\mathbf{Area = (a - 5)(a^2 + 5a + 25)}$

The area of a rectangle is:

$\mathbf{Area = Length \times Width}$

So, by comparison:

$\mathbf{Length = a -5}$

$\mathbf{Width = a^2 + 5a + 25}$

Read more about areas at:

brainly.com/question/3518080

6 0

1 year ago