Ask question

Ask question

All categories

2 years ago

12

Suppose that two balanced, six sided dice are tossed repeatedly and the sum of the two uppermost faces is determined on each tos

s. (a) What is the probability that we obtain a sum of 3 before we obtain a sum of 7

1 answer:

Simora [160]2 years ago

6 0

Answer:

$\frac{(2/36)}{(1-(28/36))} = 1/4$

Step-by-step explanation:

You might be interested in

If 90 percent of automobiles in Orange County have both headlights working, what is the probability that in a sample of eight au

Alex17521 [72]

Answer:

$P(X \geq 7) = P(X=7) +P(X=8)$

And we can find the individual probabilities using the probability mass function

$P(X=7)=(8C7)(0.9)^7 (1-0.9)^{8-7}=0.3826$

$P(X=8)=(8C8)(0.9)^8 (1-0.9)^{8-8}=0.4305$

And replacing we got:

$P(X \geq 7) = P(X=7) +P(X=8)=0.3826 +0.4305=0.8131$

Step-by-step explanation:

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".

Solution to the problem

Let X the random variable of interest "number of automobiles with both headligths working", on this case we now that:

$X \sim Binom(n=8, p=0.9)$

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 for this case we want to find this probability:

$P(X \geq 7) = P(X=7) +P(X=8)$

And we can find the individual probabilities using the probability mass function

$P(X=7)=(8C7)(0.9)^7 (1-0.9)^{8-7}=0.3826$

$P(X=8)=(8C8)(0.9)^8 (1-0.9)^{8-8}=0.4305$

And replacing we got:

$P(X \geq 7) = P(X=7) +P(X=8)=0.3826 +0.4305=0.8131$

3 0

2 years ago

Read 2 more answers

Help me I don’t know the answer

Vika [28.1K]

Answer:

It is C and D :)

Step-by-step explanation:

Each input is multiplied by 2 to get the output which is why it is C. The coordinates are just the input as the X value and the output as the Y value, which is why it is also D.

Hope this helps can I have brainliest pls

3 0

2 years ago

Help me pls with my mathh

rjkz [21]

Sure let’s see.... I believe it is D, but I’m not 100%. Don’t give low ratings. I tried.

7 0

2 years ago

A videotape store has an average weekly gross of $1,158 with a standard deviation of $120. Let x be the store's gross during a r

statuscvo [17]

Answer:

The number of standard deviations from $1,158 to $1,360 is 1.68.

Step-by-step explanation:

Problems of normally distributed samples are 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.

In this problem, we have that:

$\mu = 1158, \sigma = 120$

The number of standard deviations from $1,158 to $1,360 is:

This is Z when X = 1360. So

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

$Z = \frac{1360 - 1158}{120}$

$Z = 1.68$

The number of standard deviations from $1,158 to $1,360 is 1.68.

3 0

2 years ago

Elimination: 3x+4y=27; 5x-3y=16

aliya0001 [1]

The solution is:
y = 3
and
x = 5

7 0

3 years ago