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3 years ago

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Provide an appropriate response. A private opinion poll is conducted for a politician to determine what proportion of the popula

tion favors decriminalizing marijuana possession. How large a sample is needed in order to be 95 % confident that the sample proportion will not differ from the true proportion by more than 4 %? A. 13 B. 601 C. 423 D. 1201

1 answer:

Aloiza [94]3 years ago

6 0

Answer:

Step-by-step explanation:

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-1/3+(-7/4) in simplist form

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Answer:

your answer will be $-\frac{25}{12}$

Step-by-step explanation:

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2 years ago

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What is 7,776 ÷ 24? This is for 30 points.

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324

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What are the two ratios that are equivalent to 2:9

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Answer:

bc

Step-by-step explanation:

2:9 is equivalent to

18: 81 because is 2*9 : 9*9

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3 years ago

13. Maria earns $8 per hour plus a 5% commission on the price

Pani-rosa [81]

Answer:

Inequality:

120 + 0.05x ≥ 200

Solution:

x ≥ $1,600

Her total weekly sales must be equal to or greater than $1,600

Step-by-step explanation:

Let x represent the weekly sales she must make to reach her goal.

Given;

Pay rate = $8

Weekly total work hours = 15 hours

Commission on sales = 5% = 0.05

Total weekly earnings is;

8×15 + 0.05×x

120 + 0.05x

Minimum Weekly target earnings = $200

So;

120 + 0.05x ≥ 200

Solving the inequality equation;

0.05x ≥ 200 - 120

0.05x ≥ 80

x ≥ 80/0.05

x ≥ 1600

x ≥ $1,600

Her total weekly sales must be equal to or greater than $1,600

6 0

3 years ago

The probability that your call to a service line is answered in less than 30 seconds is 0.75. Assume that your calls are indepen

vfiekz [6]

Answer:

a) 0.2581

b) 0.4148

c) 17

Step-by-step explanation:

For each call, there are only two possible outcomes. Either they are answered in less than 30 seconds. Or they are not. The probabilities for each call are independent. So we use the binomial probability distribution to solve this question.

Binomial probability distribution

The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

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

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

And p is the probability of X happening.

In this problem we have that:

$p = 0.75$

a. If you call 12 times, what is the probability that exactly 9 of your calls are answered within 30 seconds? Round your answer to four decimal places (e.g. 98.7654).

This is $P(X = 9)$ when $n = 12$ . So

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

$P(X = 9) = C_{12,9}.(0.75)^{9}.(0.25)^{3} = 0.2581$

b. If you call 20 times, what is the probability that at least 16 calls are answered in less than 30 seconds? Round your answer to four decimal places (e.g. 98.7654).

This is $P(X \geq 16)$ when $n = 20$

So

$P(X \geq 16) = P(X = 16) + P(X = 17) + P(X = 18) + P(X = 19) + P(X = 20)$

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

$P(X = 16) = C_{20,16}.(0.75)^{16}.(0.25)^{4} = 0.1897$

$P(X = 17) = C_{20,17}.(0.75)^{17}.(0.25)^{3} = 0.1339$

$P(X = 18) = C_{20,18}.(0.75)^{18}.(0.25)^{2} = 0.0669$

$P(X = 19) = C_{20,19}.(0.75)^{19}.(0.25)^{1} = 0.0211$

$P(X = 20) = C_{20,20}.(0.75)^{20}.(0.25)^{0} = 0.0032$

So

$P(X \geq 16) = P(X = 16) + P(X = 17) + P(X = 18) + P(X = 19) + P(X = 20) = 0.1897 + 0.1339 + 0.0669 + 0.0211 + 0.0032 = 0.4148$

c. If you call 22 times, what is the mean number of calls that are answered in less than 30 seconds? Round your answer to the nearest integer.

The expected value of the binomial distribution is:

$E(X) = np$

In this question, we have $n = 22$

So

$E(X) = 22*0.75 = 16.5$

The closest integer to 16.5 is 17.

7 0

3 years ago