Alex has a set of 9 music discs from the 1970's. There are 126 total

Molly is making strawberry infused water. For each ounce of strawberry juice, she uses three times as many ounces of water. How

mote1985 [20]

Answer:

21 ounces of juice.

63 ounces of water

Step-by-step explanation:

let :

x = ounces of strawberry juice to make the strawberry infused water.

3x = ounces of water needed to make the strawberry infused water.

3x + x = 84

4x = 84

divide both sides of the equation by 4

x = 21 ounces

3x = 3 x 21 = 63 ounces

3 0

3 years ago

In a college student poll, it is of interest to estimate the proportion p of students in favor of changing from a quarter-system

Contact [7]

Answer:

n=206

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

The population proportion have the following distribution

$p \sim N(p,\sqrt{\frac{\hat p(1-\hat p)}{n}})$

Solution to the problem

In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 99% of confidence, our significance level would be given by $\alpha=1-0.99=0.01$ and $\alpha/2 =0.005$ . And the critical value would be given by:

$t_{\alpha/2}=-2.58, t_{1-\alpha/2}=2.58$

The margin of error for the proportion interval is given by this formula:

$ME=z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}$ (a)

And on this case we have that $ME =\pm 0.09$ , we can use as prior estimate of p 0.5, since we don't have any other info provided, and we are interested in order to find the value of n, if we solve n from equation (a) we got:

$n=\frac{\hat p (1-\hat p)}{(\frac{ME}{z})^2}$ (b)

And replacing into equation (b) the values from part a we got:

$n=\frac{0.5(1-0.5)}{(\frac{0.09}{2.58})^2}=205.44$

And rounded up we have that n=206

3 0

3 years ago

identify the range of the function shown in the graph A. {-2,2} B. y is all real numbers C. -20

Mekhanik [1.2K]

Answer:

all real numbers

Step-by-step explanation:

range is the possible y values, the graph stretches from negative infinity to positive infinity.

8 0

3 years ago

5. A student measures the velocity of the water in

Oksana_A [137]

Answer:

The percent deviation = 16.67%

Step-by-step explanation:

Please kindly check the attached for more information

8 0

3 years ago

4. Automobile policies are separated into two groups: low-risk and high-risk. Actuary Rahul examines low-risk policies, continui

ANTONII [103]

Answer:

Step-by-step explanation:

for n ∈ N

Since Actuary Rahul examines low-risk policies, continuing until a policy with a claim is found and then stopping.

∴ the probability that Actuary Rahul examines exactly n policies

$(0.9)^{n-1}.(0.1)---(1)$

the probability that Actuary Toby examines more than exactly n policies

$(0.8)^n---(2)$

Given that policies are actually independent

∴ the probability that the event (1) and (2) happens simultaneously is

$(0.9)^{n-1}*(0.1)*(0.8)^n$

∴ the probability that Actuary Rahul examines fewer policies than Actuary Toby

$\sum ^\infty _{n=1} (0.9)^{n-1}*(0.1)*(0.8)^n\\\\=(\frac{0.1}{0.9} \sum ^\infty _{n=1}(0.72)^n\\\\=\frac{1}{9} (\frac{0.72}{0.28} )\\\\=\frac{2}{7} \\\\=0.2857$

<h3>the probability that Actuary Rahul examines fewer policies than Actuary Toby is 0.2857</h3>

5 0

3 years ago