PLEASE HELP IM OFFERING 15PTS AND BRAINLIEST ANSWER. PLEASE SHOW YOUR WORK

Assume that random guesses are made for seven multiple choice questions on an SAT test, so that there are nequals7 trials, eac

Ket [755]

Answer:

$P(X < 4)=0.1335+0.3115+0.3115+0.1730=0.9295$

Step-by-step explanation:

Question assumed: Find the probability that the number x of correct answers is fewer than 4.

1) Previous concepts

The binomial distribution is a "DISCRETE probability distribution that summarizes the probability that a value will take one of two independent values under a given set of parameters. The assumptions for the binomial distribution are that there is only one outcome for each trial, each trial has the same probability of success, and each trial is mutually exclusive, or independent of each other".

2) Solution to the problem

Let X the random variable of interest, on this case we now that:

$X \sim Binom(n=7, p=0.25)$

The probability mass function for the Binomial distribution is given as:

$P(X)=(nCx)(p)^x (1-p)^{n-x}$

Where (nCx) means combinatory and it's given by this formula:

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

And we want to find this probability:

$P(X < 4)=P(X=0)+P(X=1)+P(X=2)+P(X=3)$

$P(X=0)=(7C0)(0.25)^0 (1-0.25)^{7-0}=0.1335$

$P(X=1)=(7C1)(0.25)^1 (1-0.25)^{7-1}=0.3115$

$P(X=2)=(7C2)(0.25)^2 (1-0.25)^{7-2}=0.3115$

$P(X=3)=(7C3)(0.25)^3 (1-0.25)^{7-3}=0.1730$

$P(X < 4)=0.1335+0.3115+0.3115+0.1730=0.9295$

3 0

4 years ago

Factoring Trinomials: Factor t^2-4x+3

vova2212 [387]

3 + t^2 - 4 x there no further factor.

3 0

3 years ago

If point U is reflected across the x = -3, what are the coordinates of its reflection image?

Elena L [17]

The coordinates of U after the reflection are: (-5, -3)

<h3>How to get the coordinates after the reflection?</h3>

By looking at the graph, we can see that the coordinates of point U are:

U = (-1, -3)

And we want to reflect it across the line x = -3.

Notice that because this is a vertical line, the y-component does not change by the reflection. Only changes the x-component, such that the distance between the original coordinates and the final coordinates to the line don't change.

The original x-component is x = -1, the distance to the line is:

d = |-3 - (-1)| = 2 units.

Then the new x-component will also be at 2 units of the line, but in the other direction:

new x-component: x = -3 - 2 = -5

The coordinates of U after the reflection are:

(-5, -3)

If you want to learn more about reflections:

brainly.com/question/4289712

#SPJ1

5 0

2 years ago

Is (1,-4) a solution to the equation y=-2/?<br> A yes<br> В. no

Alex

Answer: B.no

Step-by-step explanation:

To figure this out, plug (1, -4) into the equation y=-2x. 1 is the x value, so we plug it into the x. -4 is the y value, so we plug it into the y spot. In the end we get -4=-2(1). Is this true? No, it isn't. Therefore it is not an answer

7 0

3 years ago

Y = 4/2 x - 4 y intercept and the slope

Komok [63]

Answer:

y intercept is (0,-4) slope is 4/2

Step-by-step explanation:

If you plug 0 into x you get the y-intercept, because to for a y-intercept x=0.

The slope is the number attached to the x.

5 0

4 years ago