Four more than three times a number is equal to 25. What is the number?

HELPPPPP ITS URGENTTTTT<br><br> click on the photo

ArbitrLikvidat [17]

Answer:

x=67.4

Step-by-step explanation:

well sin30:1/2

So y is not 30 since 5/13 doesn’t equal 1/2

So it’s either the the third or fourth option

And x>y

So option 4 is correct

7 0

2 years ago

One-half a number minus 6 is 4

stich3 [128]

Answer:

the answer is 20

20/2 = 10

10- 6 =4

5 0

3 years ago

The probability of flu symptoms for a person not receiving any treatment is 0.038. In a clinical trial of a common drug used to

alexgriva [62]

Answer:

36.32% probability that at least 47 people experience flu symptoms. This is not an unlikely event, so this suggests that flu symptoms are not an adverse reaction to the drug.

Step-by-step explanation:

I am going to use the normal approximation to the binomial 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:

$n = 1164, p = 0.038$

So

$\mu = E(X) = np = 1164*0.038 = 44.232$

$\sigma = \sqrt{V(X)} = \sqrt{np(1-p)} = 6.5231$

Estimate the probability that at least 47 people experience flu symptoms.

Using continuity correction, this is $P(X \geq 47 - 0.5) = P(X \geq 46.5)$ , which is 1 subtracted by the pvalue of Z when X = 46.5.

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

$Z = \frac{46.5 - 44.232}{6.5231}$

$Z = 0.35$

$Z = 0.35$ has a 0.6368

1 - 0.6368 = 0.3632

36.32% probability that at least 47 people experience flu symptoms. This is not an unlikely event, so this suggests that flu symptoms are not an adverse reaction to the drug.

6 0

3 years ago

Cound someone please help me on this, I'm stuck.

Katyanochek1 [597]

Negative exponents work like this:

$a^{-b}=\dfrac{1}{a^b}$