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Debora [2.8K]
2 years ago
15

According to a Wired magazine article, of e-mails that are received are tracked using software that can tell the e-mail sender w

hen, where, and on what type of device the e-mail was opened (Wired magazine website). Suppose we randomly select received e-mails.

Mathematics
1 answer:
VladimirAG [237]2 years ago
8 0

Answer:

a. 12

b. 7.200 and 2.683

Step-by-step explanation:

The computation is shown below:

Given that

P = 0.40 and n = 30

a)

The expected value of received e-mails is

= n × p

= 30 × 0.4

= 12  

b)

The variance of emails received is

= n × p × (1 - p)

= 30 × 0.4 × 0.6

= 7.200

Now

The standard deviation of emails received is

= sqrt(variance)

= 2.683

We simply applied the above formula

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Answer:

if i can be brainliest that would be great

f(x) = x^2+3x-10

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f(x+5) = (x^2+10x+25)+3(x+5)-10

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f(x+5) = x^2+13x+30

Compare this with x^2+kx+30 and we see that k = 13

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2 years ago
Shawn purchased $87.06 worth of merchandise at a department store. He gave the clerk $100. Round to the nearest whole dollar to
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Answer:

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Step-by-step explanation:

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Michael went to the grocery store and bought bottles of soda and bottles of juice. Each bottle of soda has 40 grams of sugar and
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Approximately 80,000 marriages took place in the state of New York last year. Estimate the probability that for at least one of
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Answer:

a)0,45119

b)1

Step-by-step explanation:

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B)  Now want to find the

probability that both partners celebrated their birthday on th, assuming that the year is 52 weeks and therefore 52 thursday

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P(X ≥ 1) =

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P(X ≥ 1) = 1

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