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3 years ago

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A drug trial is testing the effectiveness of two drugs. If 50 patients are given Drug A, 20 patients are given Drug B, and 100 p

atients are given a placebo, what is the probability that a patient will NOT be given a placebo?
A. 5/17
B. 10/17
C.2/17
D.7/17

1 answer:

Vsevolod [243]3 years ago

6 0

So, to find the answer you'd first add up how many patients you have:
20+50+100 = 170.
In a fraction your total would go on the bottom. Then you'd take how many patients are taking a real drug, which is represented by 20+50 = 70. This number would go on top.

So, the probability of a patient NOT getting a placebo is 70/170. Simplified would be 7/17.

The answer is D. 7/17.

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Answer:

Step-by-step explanation:

47= 3/44, so ratio is 3/44 for non-nuts muffins

Which mean, for every 44 muffins we would have 3 non-nuts muffins.

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Answer:

The bird will take 0.88 seconds to reach a height of 40 feet in the air for the first time

Step-by-step explanation:

we have

$h=-16t^2+55t+4$

This is a vertical parabola open downward

The vertex represent a maximum

where

h is the height of the bird

t is the amount of time, in seconds, the bird had been in the air

For h=40 ft

substitute in the quadratic equation

$40=-16t^2+55t+4$

$-16t^2+55t+4-40=0$

$-16t^2+55t-36=0$

The formula to solve a quadratic equation of the form

$ax^{2} +bx+c=0$

is equal to

$x=\frac{-b\pm\sqrt{b^{2}-4ac}} {2a}$

in this problem we have

$-16t^2+55t-36=0$

so

$a=-16\\b=55\\c=-36$

substitute in the formula

$x=\frac{-55\pm\sqrt{55^{2}-4(-16)(-36)}} {2(-16)}$

$x=\frac{-55\pm\sqrt{721}} {-32}$

$x=\frac{-55+\sqrt{721}} {-32}=0.88\ sec$

$x=\frac{-55-\sqrt{721}} {-32}=2.56\ sec$

therefore

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3 years ago

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The height is 2 inches

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3 years ago

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Answer:

0.7588 = 75.88% probability that more than 1 vessel transporting nuclear weapons was destroyed

Step-by-step explanation:

The vessels are destroyed without replacement, which means that the hypergeometric distribution is used to solve this question.

Hypergeometric distribution:

The probability of x successes is given by the following formula:

$P(X = x) = h(x,N,n,k) = \frac{C_{k,x}*C_{N-k,n-x}}{C_{N,n}}$

In which:

x is the number of successes.

N is the size of the population.

n is the size of the sample.

k is the total number of desired outcomes.

Combinations formula:

$C_{n,x}$ is the number of different combinations of x objects from a set of n elements, given by the following formula.

$C_{n,x} = \frac{n!}{x!(n-x)!}$

In this question:

Fleet of 17 means that $N = 17$

4 are carrying nucleas weapons, which means that $k = 4$

9 are destroyed, which means that $n = 9$

What is the probability that more than 1 vessel transporting nuclear weapons was destroyed?

This is:

$P(X > 1) = 1 - P(X \leq 1)$

In which

$P(X \leq 1) = P(X = 0) + P(X = 1)$

So

$P(X = x) = h(x,N,n,k) = \frac{C_{k,x}*C_{N-k,n-x}}{C_{N,n}}$

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$P(X = 1) = h(1,17,9,4) = \frac{C_{4,1}*C_{13,8}}{C_{17,9}} = 0.2118$

Then

$P(X \leq 1) = P(X = 0) + P(X = 1) = 0.0294 + 0.2118 = 0.2412$

$P(X > 1) = 1 - P(X \leq 1) = 1 - 0.2412 = 0.7588$

0.7588 = 75.88% probability that more than 1 vessel transporting nuclear weapons was destroyed

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Answer:

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Step-by-step explanation:

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