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andrezito [222]

3 years ago

10

The weight of male Americans between the ages of 18 and 25 is normally distributed, with a mean of 160.4 lb and a standard devia

tion of 27 lb. One definition of obesity states that a person is obese if the z-score of his or her weight is greater than 2. What is the obesity threshold weight for a young adult American male? Round your answer to the nearest tenth. A. 200.9 lb B. 187.4 lb C. 173.9 lb D. 214.4 lb

2 answers:

torisob [31]3 years ago

6 0

you need to substitute.... then do: 160.4(mean)+2(x)*27(z)= 214.4lb

Nataliya [291]3 years ago

3 0

Answer:

Step-by-step explanation:

We know that $z=\frac{x-{\mu}}{\sigma}$ (1)

and also we are given that a person is obese if the z-score of his or her weight is greater than 2.

Thus, using this information we can rewrite the above equation (1),

$2\geq\frac{x-160.4}{27}$

Solving this equation, we have

⇒ $54\geq(x-160.4)$

⇒ $54+160.4\geq x$

⇒ $214.4\geq x$

Thus, the obesity threshold weight for a young adult American male is $214.4lb\geq x$ .

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vitfil [10]

Answer:

(A) $e^2$

(b) $e^{-3}$

(c) $e^2$

(d) $e^3$

Step-by-step explanation:

We have given expression and we have to simplify the expression using exponent property

(A) $(\frac{1}{e})^{-2}$

So $(\frac{1}{e})^{-2}=\frac{1}{e^{-2}}=e^2$

(b) $(\frac{e^5}{e^2})^{-1}$

So $(\frac{e^5}{e^2})^{-1}=(e^{3})^{-1}=e^{-3}$

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3 years ago

Passes through (1,12) and has a vertex (10,-4)

agasfer [191]

Answer: 16/81 (x-10)^2 -4

Step-by-step explanation:

To write a vertex equation with just a point and the vertex, you have to figure out the variables.

In vertex form, the equation is y = a (x-h)^2 + k

Your y is 12, x = 1, h = 10, and k = -4

Plug everything into equation

12 = a (1 - 10)^2 -4

12 = a (-9)^2 - 4

12 = 81a - 4

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16/81 = a

Now you know what the 'a' value is.

If you graph 16/81 (x-10)^2 -4 , you will get a point at (1,12) and a vertex of (10,-4)!

I hope this helps!

3 0

3 years ago

The life of a red bulb used in a traffic signal can be modeled using an exponential distribution with an average life of 24 mont

BartSMP [9]

Answer:

See steps below

Step-by-step explanation:

Let X be the random variable that measures the lifespan of a bulb.

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The probability that the bulb fails the first year is

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• If the bulb is in good condition at the end of 18 months, what is the probability that the bulb will be in good condition at the end of 24 months?

Let A and B be the events,

A = “The bulb will last at least 24 months”

B = “The bulb will last at least 18 months”

We want to find P(A | B).

By definition P(A | B) = P(A∩B)P(B)

but B⊂A, so A∩B = B and

$\bf P(A | B) = P(B)P(B) = (P(B))^2$

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• If the signal has six red bulbs, what is the probability that at least one of them needs replacement at the first inspection? Assume distribution of lifetime of each bulb is independent

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<em>Probability that at least one of them needs replacement at the first inspection = 1- probability that none of them needs replacement at the first inspection. </em>

This means that,

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Rainbow [258]

Answer: (-3,0)

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3 years ago

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gulaghasi [49]

Answer:

72°

Step-by-step explanation:

Given

Zy = 108°

Zx = ?

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Zx + 108° = 180°

Zx = 180° - 108°

Zx = 72°

Hope it will help :)

4 0

3 years ago