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3 years ago

11

it was found that out of 45 girls,10 joined singing but not dancing and 24 joined singing.How many joined both. options: A: 21 B

:34 C: 14 D:24

1 answer:

katrin [286]3 years ago

3 0

Answer:

answer is 24

out of 45,

24+10=singing

only 24=dancing

so 24 girls joined both

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Past records indicate that the probability of online retail orders

Tcecarenko [31]

Answer:

a) Mean = 1.6, standard deviation = 1.21

b) 18.87% probability that zero online retail orders will turn out to be fraudulent.

c) 32.82% probability that one online retail order will turn out to be fraudulent.

d) 48.31% probability that two or more online retail orders will turn out to be fraudulent.

Step-by-step explanation:

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.

The mean of the binomial distribution is:

$E(X) = np$

The standard deviation of the binomial distribution is:

$\sqrt{V(X)} = \sqrt{np(1-p)}$

In this problem, we have that:

$p = 0.08, n = 20$

a. What are the mean and standard deviation of the number of online retail orders that turn out to be fraudulent?

Mean

$E(X) = np = 20*0.08 = 1.6$

Standard deviation

$\sqrt{V(X)} = \sqrt{np(1-p)} = \sqrt{20*0.08*0.92} = 1.21$

b. What is the probability that zero online retail orders will turn out to be fraudulent?

This is P(X = 0).

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

$P(X = 0) = C_{20,0}.(0.08)^{0}.(0.92)^{20} = 0.1887$

18.87% probability that zero online retail orders will turn out to be fraudulent.

c. What is the probability that one online retail order will turn out to be fraudulent?

This is P(X = 1).

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

$P(X = 1) = C_{20,1}.(0.08)^{1}.(0.92)^{19} = 0.3282$

32.82% probability that one online retail order will turn out to be fraudulent.

d. What is the probability that two or more online retail orders will turn out to be fraudulent?

Either one or less is fraudulent, or two or more are. The sum of the probabilities of these events is decimal 1. So

$P(X \leq 1) + P(X \geq 2) = 1$

We want $P(X \geq 2)$

So

$P(X \geq 2) = 1 - P(X \leq 1)$

In which

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

From itens b and c

$P(X \leq 1) = 0.1887 + 0.3282 = 0.5169$

$P(X \geq 2) = 1 - P(X \leq 1) = 1 - 0.5169 = 0.4831$

48.31% probability that two or more online retail orders will turn out to be fraudulent.

4 0

3 years ago

PLS HALP ME!!!!!! You have $6.50 to make copies. Each copy costs $0.45. Write and solve an inequality that represents the number

serious [3.7K]

Step-by-step explanation:

Variable x = number of copies

6.50 <= 0.45x

Divide both sides by 0.45

6.50 ÷ 0.45 <= 0.45x ÷ 0.45

14.4444.... <= x

No more than 14 copies

6.50 <= 0.45x

6.50 <= 0.45(14.444)

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3 years ago

Can someone help on number 32 please

STatiana [176]

Answer:

$b. -2.5, -\frac{5}{4}, -\frac{2}{3}, 0.75, \sqrt{3}, 1.9, I-4I$

Step-by-step explanation:

-5/4 is smaller than -2/3 since on the negative sides, any number who is larger is smaller.

0.75 is smaller than the square root of 3 since that equals to 1.7.

1.9 is smaller than the absolute value of -4 since that equals to 4.

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3 years ago

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What is 1230*456

Marta_Voda [28]

Answer:

560880

Step-by-step explanation:

THERE

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2 years ago

What is the prime factorization of 43? Enter your answer as a product of prime numbers, like 2 x 3 or as a single prime number,

storchak [24]

Answer:

43

Step-by-step explanation:

43 is a prime number

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2 years ago