Can someone please help me with math.

Divide 2 1/2 divided by 1/5 in simplest form

Strike441 [17]

Answer:

10

Step-by-step explanation:

first u take 2 1/2 and change it into a improper fraction.

so 2 X 2 = 4 then + 1

=5

5/2 divide by 1/4

which is 10

3 0

2 years ago

Read 2 more answers

Plz help question below

bearhunter [10]

Plan A costs a total of $95 since it says $95 for unlimited talk and text.

Plan B:
(.10 x 800) + (.05 x 1000)
The (.10 x 800) represents 10 cents per talk minute for 800 minutes.
The (.05 x 1000) represents 5 cents per text message for 1000 text messages.
Solve:
.10 x 800 = 80
.05 x 1000 = 50
80 + 50 = 130
This means Plan B will cost him $130 under these conditions.

Plan C:
20 + ((.05 x 800)+(.05 x 1000))
The 20 + represents a flat rate of $20 per month.
The (.05 x 800) represents 5 cents per call minute.
The (.05 x 1000) represents 5 cents per text.
Solve:
.05 x 800 = 40
.05 x 1000 = 50
20 + 40 + 50 = 110
This means Plan C will cost him $110 under these conditions.

Plan D:
45 + (.10(800 - 500))
The 45 + represents a flat monthly rate of $45.
The (800 - 500) represents how many minutes he has to pay for with the 500 free.
The .10 is the cost per extra minute.
Solve:
800 - 500 = 300
.10 x 300 = 30
45 + 30 = 75
This means Plan D will cost him $75 under these conditions.

In short:
Plan A- $95
Plan B- $130
Plan C- $110
Plan D- $75
The least expensive among these is Plan D, which only costs $75 per month.

5 0

3 years ago

It takes one week for a crew of workers to pave 3/5 kilometer of a road. At that rate, how long will it take to pave 1 kilometer

Flauer [41]

Answer:

1.67 weeks

Step-by-step explanation:

Let X= time it will take to pave 1 kilometer?

1 week=3/5 kilometer

X week =1 kilometer

Cross multiply

3/5 X= 1

3X= 5

X= 5/3

1.67 weeks

8 0

3 years ago

In a study of 420,095 Danish cell phone users, 135 subjects developed cancer of the brain or nervous system (based on data from

Maksim231197 [3]

Answer:

$z=\frac{0.0003214 -0.00034}{\sqrt{\frac{0.00034(1-0.00034)}{420095}}}=-0.654$

$p_v =2*P(Z$

So the p value obtained was a very high value and using the significance level given $\alpha=0.005$ we have $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can say that the true proportion not differs significantly from the specified value of 0.00034 or 0.034%.

Step-by-step explanation:

1) Data given and notation

n=420095 represent the random sample taken

X=135 represent the subjects developed cancer of the brain or nervous system (based on data from the Journal of the National Cancer Institute as reported in USA Today)

$\hat p=\frac{135}{420095}=0.0003214$ estimated proportion of subjects developed cancer of the brain or nervous system (based on data from the Journal of the National Cancer Institute as reported in USA Today)

$p_o=0.00034$ is the value that we want to test

$\alpha=0.005$ represent the significance level

Confidence=99.5% or 0.995

z would represent the statistic (variable of interest)

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

2) Concepts and formulas to use

We need to conduct a hypothesis in order to test the claim that the brain or nervous system at a rate that is different from the rate of 0.0340% :

Null hypothesis: $p=0.00034$

Alternative hypothesis: $p \neq 0.00034$

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 $p_o$ .

3) Calculate the statistic

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

$z=\frac{0.0003214 -0.00034}{\sqrt{\frac{0.00034(1-0.00034)}{420095}}}=-0.654$

4) 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 $\alpha=0.005$ . The next step would be calculate the p value for this test.

Since is a bilateral test the p value would be:

$p_v =2*P(Z$

So the p value obtained was a very high value and using the significance level given $\alpha=0.005$ we have $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can say that the true proportion not differs significantly from the specified value of 0.00034 or 0.034%.

4 0

3 years ago

Which expression has the same value as 4÷25 in fraction form

otez555 [7]

Answer:

4/25

Step-by-step explanation:

It is a fraction with 4 in the numerator and 25 in the denominator.

4

__

25

6 0

2 years ago