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3 years ago

Cant figure how to answer this

Mathematics

1 answer:

Aleksandr-060686 [28]3 years ago

4 0

Answer:

-5(2) (-2) +2 + 4(-2) +7 = 21

-4(2) -2(-2) -10 = -14

21/14 = -1.5 or -1 1/2

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What is the equation of the line shown in this graph?

Vika [28.1K]

Answer:

y=1

Step-by-step explanation:

since there is no slope all you have is the y intercept so all you have to put is the y-intercept. That easy!

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3 years ago

Please help, need answer fast!

AleksandrR [38]

The answer is
B. 13ab

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3 years ago

The pregnancy length in days for a population of new mothers can be approximated by a normal distribution with a mean of days an

solniwko [45]

Answer:

(a) 283 days

(b) 248 days

Step-by-step explanation:

The complete question is:

The pregnancy length in days for a population of new mothers can be approximated by a normal distribution with a mean of 268 days and a standard deviation of 12 days. (a) What is the minimum pregnancy length that can be in the top 11% of pregnancy lengths? (b) What is the maximum pregnancy length that can be in the bottom 5% of pregnancy lengths?

Solution:

The random variable X can be defined as the pregnancy length in days.

Then, from the provided information $X\sim N(\mu=268, \sigma^{2}=12^{2})$ .

(a)

The minimum pregnancy length that can be in the top 11% of pregnancy lengths implies that:

P (X > x) = 0.11

⇒ P (Z > z) = 0.11

⇒ z = 1.23

Compute the value of x as follows:

$z=\frac{x-\mu}{\sigma}\\\\1.23=\frac{x-268}{12}\\\\x=268+(12\times 1.23)\\\\x=282.76\\\\x\approx 283$

Thus, the minimum pregnancy length that can be in the top 11% of pregnancy lengths is 283 days.

(b)

The maximum pregnancy length that can be in the bottom 5% of pregnancy lengths implies that:

P (X < x) = 0.05

⇒ P (Z < z) = 0.05

⇒ z = -1.645

Compute the value of x as follows:

$z=\frac{x-\mu}{\sigma}\\\\-1.645=\frac{x-268}{12}\\\\x=268-(12\times 1.645)\\\\x=248.26\\\\x\approx 248$

Thus, the maximum pregnancy length that can be in the bottom 5% of pregnancy lengths is 248 days.

8 0

3 years ago

A line segment has endpoints at (2,10) and (10,2). What are the coordinates of the midpoint of the line segment?

IrinaVladis [17]

Answer:

(6,6)

Step-by-step explanation:

The midpoint formula is $(\frac{x_1+x_2}{2},\frac{y_1+y_2}{2} )$ . Substitute (2,10) and (10,2) into this formula and simplify.

$(\frac{x_1+x_2}{2},\frac{y_1+y_2}{2} ) \\(\frac{2+10}{2},\frac{10+2}{2} ) \\(\frac{12}{2},\frac{12}{2} ) \\(6,6)$

8 0

4 years ago

In a random sample of 45 newborn babies, what is the probability that 40% or fewer of the sample are boys. (Use 3 decimal places

erastova [34]

Answer:

$z= \frac{p- \mu_p}{\sigma_p}$

And the z score for 0.4 is

$z = \frac{0.4-0.4}{\sigma_p} = 0$

And then the probability desired would be:

$P(p$

Step-by-step explanation:

The normal approximation for this case is satisfied since the value for p is near to 0.5 and the sample size is large enough, and we have:

$np = 45*0.4= 18 >10$

$n(1-p) = 45*0.6= 27 >10$

For this case we can assume that the population proportion have the following distribution

$p \sim N(p,\sqrt{\frac{p(1-p)}{n}})$

Where:

$\mu_{p}= \hat p = 0.4$

$\sigma_p = \sqrt{\frac{p(1-p)}(n} =\sqrt{\frac{0.4(1-0.4)}(45}= 0.0703$

And we want to find this probability:

$P(p$

And we can use the z score formula given by:

$z= \frac{p- \mu_p}{\sigma_p}$

And the z score for 0.4 is

$z = \frac{0.4-0.4}{\sigma_p} = 0$

And then the probability desired would be:

$P(p$

7 0

3 years ago

Read 2 more answers