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2 years ago

5

Jackson has 14 pet birds and rabbits. The total number of rabbits have 44 more legs than the total number of birds. How many pet

birds does he have?

1 answer:

Tcecarenko [31]2 years ago

8 0

I am unsure what you are talking about please improve your question next time please.

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a construction worker needs to put a rectangular window in the side of a building. he knows from measuring that the top and bott

Cloud [144]

The other diagonal would be 13 feet as well because it is a rectangle.

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2 years ago

Read 2 more answers

The Metro theater has 20 rows of seats with 18 seats in each row Tickets cost $5 The theaters income in dollars if all seats are

Olin [163]

Answer: $1800

The theater income will be the total of audience multiplied by the ticket cost. To answer this question, you need to determine the total audience count. Assuming all the seats are occupied then:
Total audience= row of seats x seats/ row = 20x18 people = 360 people

After that the income would be:
Income = audience x ticket cost
Income= 360 people x $5 / people= $1800

3 0

2 years ago

Tom started an entertainment company. The net value of the company (in thousands of dollars) ttt months after its creation is mo

Furkat [3]

Step-by-step explanation:

Given the expression for the net value of an entertainment company after t months modeled by the equation;

v(t)=4t²-24t-28

1) To write the expression in a factored form, we need to factorize the equation given;

v(t)=4t²-24t-28

divide through by 4

v(t)=t²-6t-7

v(t)= t²-7t+t-7

v(t)= t(t-7)+1(t-7)

v(t)= (t+1)(t-7)

Hence the function in a factored or vertex form is v(t)= (t+1)(t-7)

2) To know the number of months after the company creation that the company reaches its lowest value, we will substitute v(t) = 0 into the factored form of the expression as shown;

v(t)= (t+1)(t-7)

0 = (t+1)(t-7)

(t+1)(t-7) = 0

t+1 = 0 and t-7 = 0

t = -1 and t = 7

But t cannot be negative

Hence t = 7 months

This means that the company reaches its lowest net value after 7 months

8 0

2 years ago

In 1970 the population of the United States was 203 million. Ten years later, in 1980, the population of the United States was 2

andrezito [222]

Answer:

The exponential function for the US population is:

$y = 203\cdot e^{0.0107\cdot t}$

Step-by-step explanation:

Let be supposed that US population can be modelled by means of the following exponential function:

$y = A \cdot e^{B\cdot t}$

Where:

$t$ - Time, measured in years. Where t = 0 for 1970.

$A$ - Initial population, in millions inhabitants.

$B$ - Exponential rate constant, in years.

$y$ - Population, in millions inhabitants.

Each constant is found hereafter:

A

$203 = A \cdot e^{B\cdot 0}$

$203 = A \cdot 1$

$A = 203$

B

$226 = 203\cdot e^{B\cdot 10}$

$\frac{226}{203} = e^{10\cdot B}$

$10\cdot B = \ln \frac{226}{203}$

$B = \frac{1}{10}\cdot \ln \frac{226}{203}$

$B = 0.0107$

The exponential function for the US population is:

$y = 203\cdot e^{0.0107\cdot t}$

4 0

2 years ago

According to the WHO MONICA Project the mean blood pressure for people in China is 128 mmHg with a standard deviation of 23 mmHg

Sati [7]

Answer:

a) Mean blood pressure for people in China.

b) 38.21% probability that a person in China has blood pressure of 135 mmHg or more.

c) 71.30% probability that a person in China has blood pressure of 141 mmHg or less.

d) 8.51% probability that a person in China has blood pressure between 120 and 125 mmHg.

e) Since Z when X = 135 is less than two standard deviations from the mean, it is not unusual for a person in China to have a blood pressure of 135 mmHg

f) 157.44mmHg

Step-by-step explanation:

When the distribution is normal, we use the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

If X is two standard deviations from the mean or more, it is considered unusual.

In this question:

$\mu = 128, \sigma = 23$

a.) State the random variable.

Mean blood pressure for people in China.

b.) Find the probability that a person in China has blood pressure of 135 mmHg or more.

This is 1 subtracted by the pvalue of Z when X = 135.

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{135 - 128}{23}$

$Z = 0.3$

$Z = 0.3$ has a pvalue of 0.6179

1 - 0.6179 = 0.3821

38.21% probability that a person in China has blood pressure of 135 mmHg or more.

c.) Find the probability that a person in China has blood pressure of 141 mmHg or less.

This is the pvalue of Z when X = 141.

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{141 - 128}{23}$

$Z = 0.565$

$Z = 0.565$ has a pvalue of 0.7140

71.30% probability that a person in China has blood pressure of 141 mmHg or less.

d.)Find the probability that a person in China has blood pressure between 120 and 125 mmHg.

This is the pvalue of Z when X = 125 subtracted by the pvalue of Z when X = 120. So

X = 125

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{125 - 128}{23}$

$Z = -0.13$

$Z = -0.13$ has a pvalue of 0.4483

X = 120

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{120 - 128}{23}$

$Z = -0.35$

$Z = -0.35$ has a pvalue of 0.3632

0.4483 - 0.3632 = 0.0851

8.51% probability that a person in China has blood pressure between 120 and 125 mmHg.

e.) Is it unusual for a person in China to have a blood pressure of 135 mmHg? Why or why not?

From b), when X = 135, Z = 0.3

Since Z when X = 135 is less than two standard deviations from the mean, it is not unusual for a person in China to have a blood pressure of 135 mmHg.

f.) What blood pressure do 90% of all people in China have less than?

This is the 90th percentile, which is X when Z has a pvalue of 0.28. So X when Z = 1.28. Then

X = 120

$Z = \frac{X - \mu}{\sigma}$

$1.28 = \frac{X - 128}{23}$

$X - 128 = 1.28*23$

$X = 157.44$

So

157.44mmHg

6 0

2 years ago