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3 years ago

11

ivan plans to recognize the music on his Mp3 player . After the changes he is planning he will have 2 4/5 times as many hours of

rock and hip hop music on his mp3 player ?

1 answer:

hammer [34]3 years ago

8 0

So what do you want to know about it? We need more info on this.

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Graph 3(8-4x)<6(x-5)

Zinaida [17]

First simplify this inequality:

$3(8-4x)$

Now you can graph this inequality. Draw the vertical dashed line x=3 and shade the region to the right from this line. This is exactly the region that represents the solution of inequality (see attached diagram for details).

4 0

3 years ago

A magazine publisher mails a survey to every subscriber asking about the quality of its subscription service.

scoray [572]

A Statistic.

Since they want to know how their magazine are, they are gonna make a survey. In the survey, the people are statistics to see how well their magazines are. With that, they can decide to change their subjects or whatever it is. Hope this helps!

3 0

3 years ago

A geologist has collected 5 specimens of basaltic rock and 7 specimens of granite. The geologist instructs a laboratory assistan

MaRussiya [10]

The rocks are chosen without replacement, which means that the hypergeometric distribution is used to solve this question. First we get the parameters, and then we answer the questions. From this, we get that:

$E(X) = 5.25, Var(X) = 0.5966$
P(X < 6) = 0.9545
P(all specimens of one of the two types of rock are selected for analysis) = 0.2046.

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.

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

The mean and the variance are:

$\mu = \frac{nk}{N}$

$\sigma^2 = \frac{nk(N-k)(N-n)}{N^2(N-1)}$

We have that:

5 + 7 = 12 rocks, which means that $N = 12$

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

7 are granite, which means that $k = 7$

Question a:

$E(X) = \mu = \frac{9\times7}{12} = 5.25$

$Var(X) = \sigma^2 = \frac{9\times7(12-7)(12-9)}{12^2(12-1)} = 0.5966$

Thus:

$E(X) = 5.25, Var(X) = 0.5966$

Question b:

Since there are only 5 specimens of basaltic rock, at least 9 - 5 = 4 specimens of granite are needed, which means that:

$P(X < 6) = P(X = 4) + P(X = 5) + P(X = 6)$

In which

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

$P(X = 4) = h(4,12,9,7) = \frac{C_{7,4}*C_{5,5}}{C_{12,9}} = 0.1591$

$P(X = 5) = h(5,12,9,7) = \frac{C_{7,5}*C_{5,4}}{C_{12,9}} = 0.4773$

$P(X = 6) = h(6,12,9,7) = \frac{C_{7,6}*C_{5,3}}{C_{12,9}} = 0.3181$

Thus

$P(X < 6) = P(X = 4) + P(X = 5) + P(X = 6) = 0.1591 + 0.4773 + 0.3181 = 0.9545$

So P(X < 6) = 0.9545.

Question c:

5 of basaltic and 4 of granite: 0.1591 probability.

7 of granite is P(X = 7), in which

$P(X = 7) = h(7,12,9,7) = \frac{C_{7,7}*C_{5,2}}{C_{12,9}} = 0.0455$

0.1591 + 0.0455 = 0.2046, thus:

P(all specimens of one of the two types of rock are selected for analysis) = 0.2046.

A similar question is found at brainly.com/question/24008577

5 0

3 years ago

Which expression is equivalent to 76× + 68?

alexandr1967 [171]

Answer:

4(19x + 17)

Step-by-step explanation:

76x + 68 both numbers are divided by 4 so we fact out 4 and introduce the brackets : 4(19x + 17 )

7 0

3 years ago

Suppose you have 24 CDs. You know that you have 7 more CDs than your friend. Write and solve an equation to find the number of C

mote1985 [20]

It’s c hope this helped

8 0

3 years ago