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3 years ago

What is the answer? (Plz try to explain how to solve thx!)

Mathematics

1 answer:

slamgirl [31]3 years ago

8 0

Answer:

I think your answer would be C I am not sure the way I worked it out says C. I hope this helps you out.

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En una urna hay 200 esferas, el 25% son rojas, 1/4 son amarillas, la mitad de lo que queda son azules y el resto es verde. Calcu

masha68 [24]

Answer:

I no speak spanish

Step-by-step explanation:

6 0

3 years ago

Hannah is at the supermarket to buy carrots and potatoes. If she buys 2 pounds of carrots and 3 pounds of potatoes, it will cost

zhenek [66]

Answer:

Carrots cost $ 1.75 a pound which is more than potatoes cost.

Step-by-step explanation:

Let,

Carrots cost $ x per pound and potatoes cost $ y per pound.

Buying 2 pounds of carrots and 3 pounds of potatoes will cost her

$ $(2\times x + 3\times y)$

and

Buying 4 pounds of carrots and 4 pounds of potatoes will cost her

$ $(4\times x + 4\times y)$

According to the question,

$(2\times x + 3\times y) = 8$ -----(1)

$(4\times x + 4\times y) = 13$ -----(2)

multiplying (1) by 2 we get,

$(4\times x + 6\times y) = 16$ -----(3)

Deducting (2) from (3) we get,

$2\times y = 3$

⇒ $y = \frac{3}{2} = 1.5$ ------------------(4)

Putting value of y in (1) we get,

$(2\times x = 8 - 3\times 1.5) = 3.5$

⇒ $x =\frac{3.5}{2} = 1.75$ ------------(5)

8 0

3 years ago

Select the expression that represents a rational function.

Sati [7]

Answer:

y = (x +2)/(x -3)

Step-by-step explanation:

A rational function is a function (y = ...) that has a definition that is the ratio of two polynomials.

Of the choices listed, the one attached is the rational function.

8 0

3 years ago

The scale on a map is 2cm= 1km. Express this as a ratio

Lemur [1.5K]

This would mean that the ratio is 2:1 or 2 to 1 or also 2/1.

The ratio would be that because it's 2 centimeters per 1 kilometer.

7 0

3 years ago

A programmer plans to develop a new software system. In planning for the operating system that he will use, he needs to estimat

Vedmedyk [2.9K]

Using the z-distribution, we have that:

a) A sample of 601 is needed.

b) A sample of 93 is needed.

c) A. Yes, using the additional survey information from part (b) dramatically reduces the sample size.

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $\alpha$ , we have the following confidence interval of proportions.

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which z is the z-score that has a p-value of $\frac{1+\alpha}{2}$ .

The margin of error is:

$M = z\sqrt{\frac{\pi(1-\pi)}{n}}$

95% confidence level, hence $\alpha = 0.95$ , z is the value of Z that has a p-value of $\frac{1+0.95}{2} = 0.975$ , so $z = 1.96$ .

For this problem, we consider that we want it to be within 4%.

Item a:

The sample size is <u>n for which M = 0.04.</u>

There is no estimate, hence $\pi = 0.5$

$M = z\sqrt{\frac{\pi(1-\pi)}{n}}$

$0.04 = 1.96\sqrt{\frac{0.5(0.5)}{n}}$

$0.04\sqrt{n} = 1.96\sqrt{0.5(0.5)}$

$\sqrt{n} = \frac{1.96\sqrt{0.5(0.5)}}{0.04}$

$(\sqrt{n})^2 = \left(\frac{1.96\sqrt{0.5(0.5)}}{0.04}\right)^2$

$n = 600.25$

Rounding up:

A sample of 601 is needed.

Item b:

The estimate is $\pi = 0.96$ , hence:

$M = z\sqrt{\frac{\pi(1-\pi)}{n}}$

$0.04 = 1.96\sqrt{\frac{0.96(0.04)}{n}}$

$0.04\sqrt{n} = 1.96\sqrt{0.96(0.04)}$

$\sqrt{n} = \frac{1.96\sqrt{0.96(0.04)}}{0.04}$

$(\sqrt{n})^2 = \left(\frac{1.96\sqrt{0.96(0.04)}}{0.04}\right)^2$

$n = 92.2$

Rounding up:

A sample of 93 is needed.

Item c:

The closer the estimate is to $\pi = 0.5$ , the larger the sample size needed, hence, the correct option is A.

For more on the z-distribution, you can check brainly.com/question/25404151

8 0

2 years ago