Ask question

Ask question

All categories

3 years ago

6

In 1998 a San Diego reproductive clinic reported 49 births to 207 women under the age of 40 who had previously been unable to co

nceive.
The clinic wants to cut the stated margin of error in half. How many patients' result must be used?
A. 103

B. 25
C. 828

D. 158
E. 79

1 answer:

RUDIKE [14]3 years ago

7 0

Answer:

828

Step-by-step explanation:

To cut the margin of Error in half, the clinic needs quadruple of the sample size.

If the sample size is 207 women,

Then quadruple of 207 = 4 * 207 = 828

You might be interested in

Explain why the product of a nonzero rational number and an irrational number is irrational

spayn [35]

Answer:

If you multiply any irrational number by the rational number zero, the result will be zero, which is rational. Any other situation, however, of a rational times an irrational will be irrational.

3 0

3 years ago

the atomic number and atomic weight of chlorine element is 17 and 35 respectively. Calculate the number of proton, neutron and e

laila [671]

No of protons=Atomic No=17
No of electrons=No of protons=17
No of neutrons=Massno-No of protons

$\\ \sf\longmapsto 35-17$

$\\ \sf\longmapsto 18neutrons$

6 0

3 years ago

Read 2 more answers

Factor. Explain.<br> 24x³y²-4x²y+84x^4

Elan Coil [88]

Answer:

$\boxed{\bold{4x^2\left(6xy^2-y+21x^2\right)}}$

Step By Step Explanation:

Apply Exponent Rule $\bold{\:a^{b+c}=a^ba^c}$

$\bold{x^4=x^2x^2,\:x^3y^2=x^2x}$

$\bold{24x^2x-4x^2y+84x^2x^2}$

Rewrite 84: $\bold{21\cdot \:4}$

Rewrite 24: $\bold{6\cdot \:4}$

$\bold{6\cdot \:4x^2x-4x^2y+21\cdot \:4x^2x^2}$

Factor Out Common Term $\bold{4x^2}$

$\bold{4x^2\left(6xy^2-y+21x^2\right)}$

➤ $\boxed{\bold{Mordancy}}$

6 0

3 years ago

A pair of linear equations is shown below:

trapecia [35]

That would be option D

The y intercepts are 1 and 4 and the slope are -1 and 2.

5 0

3 years ago

Read 2 more answers

When we toss a coin, there are two possible outcomes: a head or a tail. Suppose that we toss a coin 100 times. Estimate the appr

marin [14]

Answer:

96.42% probability that the number of tails is between 40 and 60.

Step-by-step explanation:

I am going to use the binomial approximation to the normal to solve this question.

Binomial probability distribution

Probability of exactly x sucesses on n repeated trials, with p probability.

Can be approximated to a normal distribution, using the expected value and the standard deviation.

The expected value of the binomial distribution is:

$E(X) = np$

The standard deviation of the binomial distribution is:

$\sqrt{V(X)} = \sqrt{np(1-p)}$

Normal probability distribution

Problems of normally distributed samples can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

When we are approximating a binomial distribution to a normal one, we have that $\mu = E(X)$ , $\sigma = \sqrt{V(X)}$ .

In this problem, we have that:

100 tosses, so $n = 100$

Two outcomes, both equally as likely. So $p = \frac{1}{2} = 0.5$

So

$E(X) = np = 100*0.5 = 50$

$\sqrt{V(X)} = \sqrt{np(1-p)} = \sqrt{100*0.5*0.5} = 5$

Estimate the approximate probability that the number of tails is between 40 and 60.

Using continuity correction.

$P(40 - 0.5 \leq X \leq 60 + 0.5) = P(39.5 \leq X \leq 60.5)$

This is the pvalue of Z when X = 60.5 subtracted by the pvalue of Z when X = 39.5. So

X = 60.5

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{60.5 - 50}{5}$

$Z = 2.1$

$Z = 2.1$ has a pvalue of 0.9821

X = 39.5

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{39.5 - 50}{5}$

$Z = -2.1$

$Z = -2.1$ has a pvalue of 0.0179

0.9821 - 0.0179 = 0.9642

96.42% probability that the number of tails is between 40 and 60.

8 0

3 years ago