Question is on the photo. Thanks!

In a lab experiment, 8700 bacteria are placed in a petri dish. The conditions are such

sesenic [268]

Answer: 28.4

Step-by-step explanation:

7 0

3 years ago

According to data from the U.S. Bureau of the Census, the approximate population y (in millions) of Los Angeles between 1950 and

dmitriy555 [2]

Answer:

The year in which the population of Los Angeles reached 2.6 million is 1965.

Step-by-step explanation:

We are given the approximate population y (in millions) of Los Angeles between 1950 and 2000 is given by:

$y = 0.0000113x^3-0.000922x^2 +0.0538x + 1.97$

y = Population(in millions)

We are supposed to find the year in which the population of Los Angeles reached 2.6 million.

Substitute y = 2.6

$2.6 = 0.0000113x^3-0.000922x^2 +0.0538x + 1.97\\2.6-1.97=0.0000113x^3-0.000922x^2 +0.0538x\\0.63=0.0000113x^3-0.000922x^2 +0.0538x$

The real solution is x=14.77≈15

We are given that 0 corresponds to 1950.

So, 15 corresponds to 1965

Hence the year in which the population of Los Angeles reached 2.6 million is 1965.

7 0

3 years ago

Again help, i don’t understand this at all

Semenov [28]

Answer:

The difference quotient of f is 8. Option C

Explanation:

Difference Quotient

Given a function f(x), the difference quotient is defined as

$\displaystyle d=\frac{f(h+h)-f(x)}{h},\ h\neq 0$

The function provided in the question is

$f(x)=8x+1$

Find f(x+h) by substituting x by x+h:

$f(x+h)=8(x+h)+1$

$f(x+h)=8x+8h+1$

Now compute:

$\displaystyle d=\frac{8x+8h+1-(8x+1)}{h}$

Operating:

$\displaystyle d=\frac{8x+8h+1-8x-1}{h}$

Simplifying:

$\displaystyle d=\frac{8h}{h}$

d=8

A. Incorrect.

This choice is different from the answer.

B. Incorrect.

This choice is different from the answer.

C. Is correct

The difference quotient is 8 as explained above.

D. Incorrect.

This choice is different from the answer.

4 0

3 years ago

Sian bought a TV in the January sales which had been reduced by 20 per cent. If she paid £290 for it, what was the original pric

Rudik [331]

I think the anwer is 362.50

7 0

3 years ago

Read 2 more answers

The marketing manager for an automobile manufacturer is interested in determining the proportion of new compact-car owners who w

Serhud [2]

Answer:

$z=\frac{0.395 -0.3}{\sqrt{\frac{0.3(1-0.3)}{200}}}=2.932$

$p_v =2*P(z>2.932)=0.0034$

So the p value obtained was a very low value and using the significance level given $\alpha=0.01$ we have $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and we can said that at 1% of significance the proportion of people that they would have purchased the GPS navigation system is significantly different from 0.3

Step-by-step explanation:

Data given and notation

n=200 represent the random sample taken

X=79 represent the number of people that they would have purchased the GPS navigation system

$\hat p=\frac{79}{200}=0.395$ estimated proportion of people that they would have purchased the GPS navigation system

$p_o=0.3$ is the value that we want to test

$\alpha=0.01$ represent the significance level

Confidence=99% or 0.99

z would represent the statistic (variable of interest)

$p_v$ represent the p value (variable of interest)

Concepts and formulas to use

We need to conduct a hypothesis in order to test the claim that the true proportion is 0.3 or no.:

Null hypothesis: $p=0.3$

Alternative hypothesis: $p \neq 0.3$

When we conduct a proportion test we need to use the z statistic, and the is given by:

$z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}}$ (1)

The One-Sample Proportion Test is used to assess whether a population proportion $\hat p$ is significantly different from a hypothesized value $p_o$ .

Calculate the statistic

Since we have all the info requires we can replace in formula (1) like this:

$z=\frac{0.395 -0.3}{\sqrt{\frac{0.3(1-0.3)}{200}}}=2.932$

Statistical decision

It's important to refresh the p value method or p value approach . "This method is about determining "likely" or "unlikely" by determining the probability assuming the null hypothesis were true of observing a more extreme test statistic in the direction of the alternative hypothesis than the one observed". Or in other words is just a method to have an statistical decision to fail to reject or reject the null hypothesis.

The significance level provided $\alpha=0.01$ . The next step would be calculate the p value for this test.

Since is a bilateral test the p value would be:

$p_v =2*P(z>2.932)=0.0034$

So the p value obtained was a very low value and using the significance level given $\alpha=0.01$ we have $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and we can said that at 1% of significance the proportion of people that they would have purchased the GPS navigation system is significantly different from 0.3

4 0

3 years ago