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ipn [44]
2 years ago
7

Dave tried to evaluate 55 – 15 + 20 step-by-step.

Mathematics
1 answer:
Softa [21]2 years ago
3 0

Answer:

Step 2

Step-by-step explanation:

In step 2 the expression was 40+20 which would have been 60 but he might have thought addition sign was subtraction so he did 40-20 which is 20 so he is wrong made mistake in step 2

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Suppose a baby food company has determined that its total revenue R for its food is given by R = − x 3 + 39 x 2 + 945 x where R
Paraphin [41]

Answer:

35,000 units

Step-by-step explanation:

Total revenue is:

R = -x^3+39x^2+945x

The maximum revenue is attained at the production level for which the derivate of the revenue function is zero:

R = -x^3+39x^2+945x\\R'=0=-3x^2+78x+945\\x=\frac{-b\pm\sqrt{78^2-(4*(-3)*945)} }{-6}\\x_1=35\\x_2=-9

Since production cannot be negative, revenue will be at a maximum when x = 35, or when the production level is 35,000 units.

4 0
3 years ago
A manufacturer of a new medication on the market for Alzheimer's disease makes a claim that the medication is effective in 65% o
NeX [460]

Answer:

z=\frac{0.639 -0.65}{\sqrt{\frac{0.65(1-0.65)}{180}}}=-0.309  

p_v =P(z  

So the p value obtained was a very high value and using the significance level given \alpha=0.05 we have p_v>\alpha so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can said that at 5% of significance the proportion of adults with the medication was effective is not significantly less than 0.65

Step-by-step explanation:

Data given and notation

n=180 represent the random sample taken

X=115 represent the adults with the medication was effective

\hat p=\frac{115}{180}=0.639 estimated proportion of adults with the medication was effective

p_o=0.65 is the value that we want to test

\alpha=0.05 represent the significance level

Confidence=95% or 0.95

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 true proportion is less than 0.65.:  

Null hypothesis:p \geq 0.65  

Alternative hypothesis:p < 0.65  

When we conduct a proportion test we need to use the z statisitc, 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{0.639 -0.65}{\sqrt{\frac{0.65(1-0.65)}{180}}}=-0.309  

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=0.05. The next step would be calculate the p value for this test.  

Since is a left tailed test the p value would be:  

p_v =P(z  

So the p value obtained was a very high value and using the significance level given \alpha=0.05 we have p_v>\alpha so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can said that at 5% of significance the proportion of adults with the medication was effective is not significantly less than 0.65

3 0
3 years ago
PLease help, i'm struggling and can't find the answer anywhere
anastassius [24]

Answer:

1/1024

Step-by-step explanation:

It can also be written as 1/4^5 and you just have to simplify it.

3 0
3 years ago
The health department estimates that eight vials of malaria Serum will treat 100 people. at this rate, how many vials are requir
lara [203]
Using butterfly method, it is 14 vials

5 0
2 years ago
Uplift causes a portion of the Earth's surface to rise above other areas of the Earth's crust. How is the process of uplift impo
SCORPION-xisa [38]

Answer:

This Is Science Not Math So Pls Dont Post Irrelevant Things To Maths

Step-by-step explanation:

5 0
2 years ago
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