For a normal distribution with mean 47 and standard deviation 6, find the probability of obtaining a value less than 45 or greater than 49.

Answers

Answer 1

Answer:

0.7392 = 73.92% probability of obtaining a value less than 45 or greater than 49.

Step-by-step explanation:

Normal Probability Distribution

Problems of normal distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

Mean 47 and standard deviation 6

This means that [tex]\mu = 47, \sigma = 6[/tex]

Less than 45:

p-value of Z when X = 45, so:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{45 - 47}{6}[/tex]

[tex]Z = -0.3333[/tex]

[tex]Z = -0.3333[/tex] has a p-value of 0.3696.

More than 49:

1 subtracted by the p-value of Z when X = 49. So

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{49 - 47}{6}[/tex]

[tex]Z = 0.3333[/tex]

[tex]Z = 0.3333[/tex] has a p-value of 0.6304.

1 - 0.6304 = 0.3996

Less than 45 or greater than 49:

2*0.3696 = 0.7392

0.7392 = 73.92% probability of obtaining a value less than 45 or greater than 49.


Related Questions

I need to know this answe ASAP

Answers

Answer:

The function is always increasing

Step-by-step explanation:

To be increasing, the y value needs to be getting bigger as x gets bigger

This is true for all values of x

The function is increasing for all values of x

37. The trip between 2 towns is exactly 90 miles. You have gone 40% of this distance. How far have
you gone?

Answers

Answer:

36 miles

Step-by-step explanation:

We want to find 40% of 90 miles

40% * 90

.40 * 90

36 miles

Distance=90mliesTravelled distance=40℅

We have to find travelled distance inorder to find this we have to find 40℅ of 90miles

[tex]\\ \Large\sf\longmapsto 90\times 40\℅[/tex]

[tex]\\ \Large\sf\longmapsto 90\times \dfrac{40}{100}[/tex]

[tex]\\ \Large\sf\longmapsto 9\times 4[/tex]

[tex]\\ \Large\sf\longmapsto 36miles [/tex]

What is the area of the pool ?

Answers

Answer:

https://brainly.com/question/24258518

Step-by-step explanation:

the area is 400! (10x40=400)

What is the largest value of A according to the division operation given above?
A)300 B)314 C)400 D)450

Answers

Answer:

Hello,

Answer B

Step-by-step explanation:

Since A=15*20+B and B<15

The max for B is 14

==> 300+14=314

Pls help need this done hurry

Answers

Answer:

Shade 23 boxes

Step-by-step explanation:

This is the first two rows fully (all 10 boxes) and then three more from the third row.

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xxxxxxxxxx

xxx . . . . . . .

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. . . . . . . . . .

. . . . . . . . . .

. . . . . . . . . .

. . . . . . . . . .

. . . . . . . . . .

. . . . . . . . . .

The median age (in years) of the U.S. population over the decades from 1960 through 2010 is given by
f(t) = −0.2176t3 + 1.962t2 − 2.833t + 29.4 (0 ≤ t ≤ 5)
where t is measured in decades, with t = 0 corresponding to 1960.
(a) What was the median age of the population in the year 1970?
(b) At what rate was the median age of the population changing in the year 1970?
(c) Calculate f ''(1).

Answers

Considering the given function, we have that:

a) 28.31 years.

b) 0.3382 years a decade.

c) 2.6184.

What is the function?

The median age of the U.S. population in t decades after 1960 is:

f(t) = -0.2176t³ + 1.962t² - 2.833t + 29.4.

1970 is one decade after 1960, hence the median was:

f(1) = -0.2176 x 1³ + 1.962 x 1² - 2.833 x 1 + 29.4 = 28.31 years.

The rate of change was is the derivative when t = 1, hence:

f'(t) = -0.6528t² + 3.924t - 2.933

f'(1) = -0.6528 x 1² + 3.924 x 1 - 2.933 = 0.3382 years a decade.

The second derivative is:

f''(t) = -1.3056t + 3.924

Hence:

f''(1) = -1.3056 x 1 + 3.924 = 2.6184.

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According to the American Academy of Cosmetic Dentistry, 75% of adults believe that an unattractive smile hurts career success. Suppose that 25 adults are randomly selected. What is the probability that 15 or more of them would agree with the claim?

Answers

Answer:

0.9703 = 97.03% probability that 15 or more of them would agree with the claim.

Step-by-step explanation:

For each adult, there are only two possible outcomes. Either they agree with the claim, or they do not. The probability of an adult agreeing with the claim is independent of any other adult, which means that the binomial probability distribution is used 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.

[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]

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

[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]

And p is the probability of X happening.

75% of adults believe that an unattractive smile hurts career success.

This means that [tex]p = 0.75[/tex]

Suppose that 25 adults are randomly selected.

This means that [tex]n = 25[/tex]

What is the probability that 15 or more of them would agree with the claim?

This is:

[tex]P(X \geq 15) = 1 - P(X < 15)[/tex]

In which:

[tex]P(X < 15) = P(X = 0) + P(X = 1) + P(X = 2) + ... + P(X = 13) + P(X = 14)[/tex]

14 is below the mean, so we start below and go until the probability is 0. Then

[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]

[tex]P(X = 14) = C_{25,14}.(0.75)^{14}.(0.25)^{11} = 0.0189[/tex]

[tex]P(X = 13) = C_{25,13}.(0.75)^{13}.(0.25)^{12} = 0.0074[/tex]

[tex]P(X = 12) = C_{25,12}.(0.75)^{12}.(0.25)^{13} = 0.0025[/tex]

[tex]P(X = 11) = C_{25,11}.(0.75)^{11}.(0.25)^{14} = 0.0007[/tex]

[tex]P(X = 10) = C_{25,10}.(0.75)^{10}.(0.25)^{15} = 0.0002[/tex]

[tex]P(X = 9) = C_{25,9}.(0.75)^{9}.(0.25)^{16} \approx 0[/tex]

Then

[tex]P(X < 15) = P(X = 10) + P(X = 11) + P(X = 12) + P(X = 13) + P(X = 14) = 0.0002 + 0.0007 + 0.0025 + 0.0074 + 0.0189 = 0.0297[/tex]

And

[tex]P(X \geq 15) = 1 - P(X < 15) = 1 - 0.0297 = 0.9703[/tex]

0.9703 = 97.03% probability that 15 or more of them would agree with the claim.

Which of the following ordered pairs is a solution of the function f(x)=3x-1

Answers

Answer:

C

Step-by-step explanation:

Plug each ordered pair into the equation

A: 4 = 3(-1)-1

4=-3-1

This is false

B: 2= 3(-1)-1

2=-3-1

This is false

C: -4 = 3(-1)-1

-4=-3-1

This is true

Find how much money needs to be deposited now into an account to obtain $7,300 (Future Value) in 6
years if the interest rate is 2.5% per year compounded monthly (12 times per year).
The final amount is $
Round your answer to 2 decimal places

Answers

Answer:

x=  $6,284.15

Step-by-step explanation:

7300 = x(1 + .025/12)^72

x = [tex]\frac{7300}{(1 + \frac{.025}{12} )^{72} }[/tex]

x=  $6,284.15  

By Using 0,2,4,5,6 Write The Smallest Number And the Greatest Number​

Answers

Answer:

smallest is 0 and greatest is 6

simple

Answer:

0 and 6

Step-by-step explanation:

Because 0 is means nothing.And the highest number is 6

A pizza parlor has a choice of 10 toppings for its pizzas. From these 10 toppings, how many different 7-topping pizzas are possible?

Answers

Answer:

120

Step-by-step explanation:

There are 10 possible toppings to choose from, you choose 7.

Using combinatorics, it's 10!/(7! 3!), or 120.

The formula is (total amount to choose from )! divided by (amount you choose)!(amount you don't choose)!

Or search up combination formula

A combination is an arrangement of a set of numbers from a total set where the order of the set is not relevant.

The formula for combination.

= [tex]^nC_r[/tex]

= n! / r! (n -r)!

The number of possible 7-toppings for the pizza is 120.

What is a combination?

A combination is an arrangement of a set of numbers from a total set where the order of the set is not relevant.

We have,

The total number of toppings = 10.

n = 10

The number of required toppings = 7.

r = 7

The formula for combination.

= [tex]^nC_r[/tex]

= n! / r! (n -r)!

The possible number of possible 7-toppings pizzas.

= [tex]^{10}C_7[/tex]

= (10 x 9 x 8) / (3 x 2)

= 120

Thus,

n = 10 and r = 7

[tex]^{10}C_7[/tex] = 120

The number of possible 7-toppings for the pizza is 120.

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find the missing side lengths​

Answers

this is a special triangle so v = 17

u = 17√2

Answer:

v = 17

u = 17[tex]\sqrt{2}[/tex]

Step-by-step explanation:

If v = 17 (it is because it is a right triangle, so the pythagorean theorum works, and triangles are 180 degrees, so 180 - 90 = 90, so the other two angles are 45 degrees, meaning that v is the same length as 17.) then

17 ^ 2 = u ^2

289 = u^2

17 root to 2

8.113 as a fraction PLEASE HELP ME ​

Answers

Answer:

8113/1000

Step-by-step explanation:

The stem-and-leaf plot lists the ages of customers in a bookstore.

How many customers are 19 or younger?



Enter your answer in the box.

Answers

Answer:

Step-by-step explanation:

2,12,14,15,17
All of them are younger than 19

Hope this helps

a rational number between 11 and 12

Answers

Answer:

11.1

11.2

11.3

11.4

11.5

11.6

11.7

11.8

11.9

If you deposit $500 dollars “Each Month!” Into an account paying 3% interest, compounded monthly, how much would be in said account after 4 years.

Please show proper work and give a good explanation in regards as to how you got your answer

Answers

Answer:

26029.26

Step-by-step explanation:

Assuming we are investing the 500 at the end of the period and starting with 500 in the account

[ P(1+r/n)^(nt) ]+PMT × {[(1 + r/n)^(nt) - 1] / (r/n)}

PMT = the monthly payment

r = the annual interest rate (decimal)

n = the number of times that interest is compounded per year

t = the time in years

[ 500(1 + .03/12)^(4*12) ]+500 × {[(1 + .03/12)^(4*12) - 1] / .03/12)}

[ 500(1 + .0025)^(48) ]+500 × {[(1 + .0025)^(48) - 1] / .0025)}

563.66 +25465.60

About 12.5% of restaurant bills are incorrect. If 200 bills are selected at ran- dom, find the probability that at least 22 will contain an error. Is this likely or unlikely to occur

Answers

Answer:

0.7734 = 77.34% probability that at least 22 will contain an error. Probability above 50%, which means that this is likely to occur.

Step-by-step explanation:

Binomial probability distribution

Probability of exactly x successes on n repeated trials, with p probability.

Can be approximated to a normal distribution, using the expected value and the standard deviation.

The expected value of the binomial distribution is:

[tex]E(X) = np[/tex]

The standard deviation of the binomial distribution is:

[tex]\sqrt{V(X)} = \sqrt{np(1-p)}[/tex]

Normal probability distribution

Problems of normally distributed distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

When we are approximating a binomial distribution to a normal one, we have that [tex]\mu = E(X)[/tex], [tex]\sigma = \sqrt{V(X)}[/tex].

About 12.5% of restaurant bills are incorrect.

This means that [tex]p = 0.125[/tex]

200 bills are selected at random

This means that [tex]n = 200[/tex]

Mean and standard deviation:

[tex]\mu = E(X) = np = 200*0.125 = 25[/tex]

[tex]\sigma = \sqrt{V(X)} = \sqrt{np(1-p)} = \sqrt{200*0.125*0.875} = 4.677[/tex]

Find the probability that at least 22 will contain an error.

Using continuity correction, this is [tex]P(X \geq 22 - 0.5) = P(X \geq 21.5)[/tex], which is 1 subtracted by the p-value of Z when X = 21.5. So

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{21.5 - 25}{4.677}[/tex]

[tex]Z = -0.75[/tex]

[tex]Z = -0.75[/tex] has a p-value of 0.2266.

1 - 0.2266 = 0.7734

0.7734 = 77.34% probability that at least 22 will contain an error. Probability above 50%, which means that this is likely to occur.

A translation T maps point B(-2,4) onto point B (3,-1). What is the translation T?
HELP PLSS!!!!

A- (x+5, y-5)
B- (x+5, y+5)
C- (x-5, y+5)
D- (x-5, y-5)

Answers

Answer:

(x+5, y-5) is the correct answer

Step-by-step explanation:

first, take -2 and 3 on x value; when you jump from -2 to 3, your answer is positive 5

second, take 4 and -1 on y value; when you jump from 4 to -1, your answer is negative 5

hence your answer for this question is a- (x+5, y-5)

GIVING BRAINLIEST!!!!! AND ALL POINTS!!!!!!!!!!!!!!!!!!!
A right rectangular prism is packed with cubes of side length fraction 1 over 4 inch. If the prism is packed with 12 cubes along the length, 8 cubes along the width, and 5 cubes along the height, what is the volume of the prism?

fraction 2 and 3 over 4 cubic inches
fraction 3 and 3 over 4 cubic inches
fraction 7 and 1 over 4 cubic inches
fraction 7 and 1 over 2 cubic inches

Answers

Answer:

7 and 1 over 2 cubic inches ( 7 1/2 in³

Step-by-step explanation:

The height = 1/4 * 5 = 1 1/4 = 1.25

The width = 1/4 * 8 = 2

The length = 1/4 * 12 = 3

Volume = 1.25 * 2 * 3 = 2.5 * 3 = 7.5

0.5 is represented as 1/2

So answer : fraction 7 and 1 over 2 cubic inches or 7 1/2 in³

if my answer is incorrect, pls correct me!

If you like my answer and explanation, mark me as brainliest!

-Chetan K

Question 1 and 2 plz explain

Answers

Answer:

1.D

2.B

Step-by-step explanation:

1. The x intercept is the value of x when y is zero. We know that the x intercept is 0.5 so we must find a value of k that will make our rational function equal zero when x=0.5

[tex]y = \frac{k}{x + 1} - 2[/tex]

Substitute x=0.5 and y=0.

[tex]0 = \frac{k}{0.5 + 1} - 2[/tex]

[tex]0= \frac{k}{1.5} - 2[/tex]

[tex]2 = \frac{k}{1.5} [/tex]

[tex]3 = k[/tex]

D is the Answer.

2. We need to consider the function

[tex] \frac{2x}{1 - {x}^{2} } [/tex]

Since the numerator is a linear term, it will have one zero to the equation using fundamental Theorem of Algebra so C is wrong.

This is a rational function because we are dividing two polynomials by each other and q(x) or the denominator isnt zero. So D is wrong.

The denominator is a quadratic term so it will have two vertical asymptote according to the fundamental Theorem of Algebra So A is Wrong.

B is Right, the equation isnt defined at x=0 because when we plug 0 into the denominator, it doesn't equate to zero.

i need help on this PLS

Answers

I REALLY HOPE THIS HELPS! I’m sorry if this was wrong but I really believe it’s true.

Answer:

The value of P is $6.75.

Step-by-step explanation:

In the diagram to the left, we see 6 apples, and are labeled that the price is $4.50.

If the prices are proportional, that may mean that each apple has the same price. To find the price of apples in the diagram to the right, divide the total price by 6:

4.50/6 = 0.75

So the price per apple is 0.75.

As seen on the diagram, P represents the total price of 9 apples.

Multiply the price per apple by 9:

0.75 x 9 = 6.75

So the value of P is $6.75

Given the arc, name the central angle.
FG
A. ∠GQJ
B. ∠FQG
C. ∠GQI
D. ∠HQI

Answers

Answer:

B

Step-by-step explanation:

Given arc FG then the central angle is the angle at the centre subtended by FG , that is

central angle = ∠ FQG

The central angle is B i.e ∠FQG

What is central angle?

A central angle exists an angle whose vertex stands present at the center of a circle created by the two radii as the sides of the angle.

In Mathematics, an “arc” exists as a smooth curve joining two endpoints. In general, an arc exists one of the portions of a circle. It is essentially a part of the circumference of a circle. Arc exists as a part of a curve. An arc can be a portion of some other curved constitutions like an ellipse but mostly guides to a circle.

The angle substended by the arc would be ∠FQG.

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[{66 +1} 2-6].7
I need help ASAP please due Monday pre-algebra show work

Answers

Ans; 7× [2-6 { 1+66}] —> 7× [2 - 6 { 67} ] —> 7× [2-402] —> 7×[- 400] —> = – 2800

I hope I helped you ^_^

2sin^2(2x) + 1 = 3sin(2x) Solve for x with exact answers. The domain is 0 ≤ x ≤ π

Answers

Answer:

x = π/12 and x = π/4.

Step-by-step explanation:

2sin^2(2x) + 1 = 3sin(2x)

2sin^2(2x) - 3sin(2x) + 1 = 0

(2sin(2x) - 1)(sin(2x) - 1) = 0

2sin(2x) - 1 = 0

2sin(2x) = 1

sin(2x) = 1/2

When there is a variable n = π/6, sin(π/6) = 1/2 [refer to the unit circle].

2x = π/6

x = π/12

sin(2x) - 1 = 0

sin(2x) = 1

When there is a variable n = π/2, sin(π/2) = 1 [refer to the unit circle].

2x = π/2

x = π/4

Hope this helps!

Levi decides to examine the effect of fertilizer on the growth of tomato plants. He chooses four plants for his experiment and applies varying amounts of fertilizer to three of them. He does not apply fertilizer to one plant.

Over a 15-day period, the plants receive fertilizer on Days 1, 4, 7, 10, and 13. Levi measures the height of all of his plants with a meterstick on Days 3, 6, 9, 12, and 15. He also makes sure to hold all experimental factors constant except for the fertilizer.

What is the dependent variable in Levi's experiment on tomato plants?


the amount of fertilizer given to the plants


the measurements of plant height


the days fertilizer was applied


the days plant height was measured

Answers

Answer:

Number 1

Step-by-step explanation:

I can answer the first one! The dependent variable is the measurement. The days in the independent and always the X variable

Answer:

Step-by-step explanation:

The measurement of the plant height. That (presumably) is dependent on the amount of fertilizer. Everything else is held constant (such amount of water, amount of sunlight, even distance from a window (constant heat), is held the same for all plants.

Use the slope-intercept form of the linear equation to write an equation of the line with given slope and y-intercept.
Slope: -6/5 y intercept (0,8)

Answers

Answer:

5y + 6x = 40

Step-by-step explanation:

hope it is well understood?

Slope intercept- y=mx+b
m is the slope
b is the y intercept (0,y)

y=-6/5x+8

need help asap (giving brainliest)

Answers

Answer:

hhhhjhgbbbjjhjjjjjkkkkkkkk

Answer:

Step-by-step explanation:

Q1. Sobey's is the best deal

In Food Basics, having the two loaves of bread costing 4.88 would mean that (4.88 / 2) one would cost 2.44.

To find out how much three would cost, multiply 2.44 by three, and the result is 7.32, which is higher than the three loves of bread that costs 7.20 in Sobey's, which Sobey's has a better deal. 7.20 / 3 = 2.40, yet Food Basics does cost higher by 4 cents for just one.

I am not too sure about question 2, but I do hope the above question helps!

Practice Exercise 3.1 Fill in the blanks: (i) The factors of 12 are (ii) The least non-zero multiples of any number is (iii) ......... is a factor of every number. ing with Numbers​

Answers

Answer:

i.)1,2,3,4,6,12

ii).the number itself

iii.)1

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“””” HELP PLEASE “”””
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Answers

9514 1404 393

Answer:

  x = 14 cm

Step-by-step explanation:

We can only solve for x if the triangles are similar. The arrows on the left and right legs say those are parallel. Since alternate interior angles at each of the transversals are congruent, the triangles are AA similar.

ΔABC ~ ΔDEC, so we have ...

  EC/ED = BC/BA

  x/(18 cm) = (35 cm)/(45 cm)

  x = (18 cm)(7/9) = 14 cm

6. On a number line, point A has a coordinate of -6, and point B has a coordinate of 2. Which is the coordinate of point M, the midpoint of AB ?
A) 0
B) -2
C) -3
D) 4

Answers

9514 1404 393

Answer:

  B) -2

Step-by-step explanation:

The midpoint is the average of the end points.

  M = (A +B)/2

  M = (-6 +2)/2 = -4/2 = -2

The coordinate of M is -2.

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