Answer:
a) 0.0808 = 8.08% probability that the sample mean rent is greater than $2700.
b) 0.0546 = 5.46% probability that the sample mean rent is between $2450 and $2550.
c) The 25th percentile of the sample mean is of $2596.
d) |Z| = 0.3 < 2, which means it would not be unusual if the sample mean was greater than $2645.
e) |Z| = 0.3 < 2, which means it would not be unusual if the sample mean was greater than $2645.
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
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.
If |Z|>2, the measure X is considered unusual.
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
The mean monthly rent for a one-bedroom apartment without a doorman in Manhattan is $2630. Assume the standard deviation is $500.
This means that [tex]\mu = 2630, \sigma = 500[/tex]
Sample of 100:
This means that [tex]n = 100, s = \frac{500}{\sqrt{100}} = 50[/tex]
a) What is the probability that the sample mean rent is greater than $2700?
This is the 1 subtracted by the p-value of Z when X = 2700. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{2700 - 2630}{50}[/tex]
[tex]Z = 1.4[/tex]
[tex]Z = 1.4[/tex] has a p-value 0.9192
1 - 0.9192 = 0.0808
0.0808 = 8.08% probability that the sample mean rent is greater than $2700.
b) What is the probability that the sample mean rent is between $2450 and $2550?
This is the p-value of Z when X = 2550 subtracted by the p-value of Z when X = 2450.
X = 2550
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{2550 - 2630}{50}[/tex]
[tex]Z = -1.6[/tex]
[tex]Z = -1.6[/tex] has a p-value 0.0548
X = 2450
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{2450 - 2630}{50}[/tex]
[tex]Z = -3.6[/tex]
[tex]Z = -3.6[/tex] has a p-value 0.0002
0.0548 - 0.0002 = 0.0546.
0.0546 = 5.46% probability that the sample mean rent is between $2450 and $2550.
c) Find the 25th percentile of the sample mean.
This is X when Z has a p-value of 0.25, so X when Z = -0.675.
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]-0.675 = \frac{X - 2630}{50}[/tex]
[tex]X - 2630 = -0.675*50[/tex]
[tex]X = 2596[/tex]
The 25th percentile of the sample mean is of $2596.
Question d and e)
We have to find the z-score when X = 2645.
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{2645 - 2630}{50}[/tex]
[tex]Z = 0.3[/tex]
|Z| = 0.3 < 2, which means it would not be unusual if the sample mean was greater than $2645.
There is a close relationship between the air pressure inside a hurricane and its maximum sustained wind speed: y=−1.22x+1250 where x is the air pressure in millibars (kPa) and y is the wind speed in knots (nautical miles per hour).
What does the slope of the line represent?
A. the change in wind speed for every 1 kPa increase in air pressure
B. the wind speed of a hurricane with an air pressure of 1000 kPa
C. the wind speed of a hurricane with an air pressure of 0 kPa
D. the change in wind speed for every hour
Answer:
A. the change in wind speed for every 1 kPa increase in air pressure
Step-by-step explanation:
The equation of a straight line is given by:
y = mx + b;
where y, x are variables, m is the slope (rate of change) of the line and b is the y intercept (value of y when x = 0)
Given the line y=−1.22x+1250 where x is the air pressure in millibars (kPa) and y is the wind speed in knots.
The slope of the line is -1.22. The slope means that there is a decrease in wind speed by 1.22 miles per hour for every increase of 1 kPa in air pressure.
Use the definition of a Taylor series to find the first four nonzero terms of the series for f(x) centered at the given value of a. (Enter your answers as a comma-separated list.)
f(x) = 7/1+x a=2
If f(x) = 7/(1 + x), then
f (2) = 7/3
f '(x) = -7/(x + 1)² ==> f ' (2) = -7/9
f ''(x) = 14/(x + 1)³ ==> f '' (2) = 14/27
f '''(x) = -42/(x + 1)⁴ ==> f ''' (2) = -14/27
Then the Taylor series of f(x) about a = 2 is
7/3 + 1/1! (-7/9) (x - 2) + 1/2! (14/27) (x - 2)² + 1/3! (-14/27) (x - 2)³
= 7/3 - 7/9 (x - 2) + 7/27 (x - 2)² - 7/81 (x - 2)³
Find the area of a rectangle that measures 12ft by 3 1/3 ft
Answer:
40 ft^2
Step-by-step explanation:
The area of a rectangle is given by
A = l*w
=12 * 3 1/3
Change to an improper fraction
= 12 ( 3*3+1)/3
= 12 (10/3)
40
Answer:
[tex]40 {ft}^{2} [/tex]
Step-by-step explanation:
[tex]area = l \times b \\ = 12 \times 3 \frac{1}{3} \\ = 12 \times \frac{10}{3} \\ = \frac{120}{3} \\ = 40 {ft}^{2} [/tex]
An elevator is on the twelfth floor it goes down 11 floors and than up 5 floors what floor is the elevator on now
Answer:
The sixth floor
Step-by-step explanation:
Rewrite the function f(x)=16^x in four different ways, using a different base in each case.
Answer:
X=1
f(x)=16^1
=16
X=2
f(x)=16^2
256
X=3
f(x)=16^3
=4096
X=4
f(x)=16^4
=65536
Here are four different ways to rewrite the function f(x) = 16^x, using a different base for each case:
Using base 2:
f(x) = (2^4)^x = 2^(4x)
Using base 3:
f(x) = (3^2)^x = 3^(2x)
Using base 10:
f(x) = (10^(log10(16)))^x = 10^(log10(16) * x)
Using base e (natural logarithm):
f(x) = (e^(ln(16)))^x = e^(ln(16) * x)
How to explain the functionIn these rewritten forms, the exponentiation of the base is expressed as a simpler expression.
This involves the new base, which helps to illustrate the relationship between the original function and the different bases used.
Learn more about functions
https://brainly.com/question/11624077
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An item is regularly priced at$15.It is now priced at a discount of55%off the regular price
Answer:
$6.75
Step-by-step explanation:
The regular price is $15 dollars. The discount is 55% off the $15.
15 * 0.55 = 8.25
15 - 8.25 = 6.75
Hope this helps.
Answer:
discount =8.25
New price 6.75
Step-by-step explanation:
15 is the regular price
The discount is 55%
15*.55
8.25
The new price is the regular price minus the discount
15-8.25
6.75
round 3/5 to 3 decimal points
Answer:
3/5=0.600
Step-by-step explanation:
I hope this answer helps
The answer is 0.6.
Upto 3 decimal places it is 0.600.
Determine the area of the given parallelogram with length 11 and altitude five
9514 1404 393
Answer:
55 square units
Step-by-step explanation:
The area of a parallelogram is the product of base length and height:
A = bh
A = (11)(5) = 55 . . . area of the given parallelogram in square units
when solving inequalities,name 2 steps that are the same as solving equations and one difference
9514 1404 393
Explanation:
same:
the addition property of equalitythe multiplication property of equality (for positive multipliers)different:
the multiplication property of equality for negative multipliers_____
Additional comment
Multiplication by a negative number has the effect of re-ordering numbers:
-1 < 2 . . . 1 > -2 (both sides multiplied by -1)
Other functions can have the same effect, so care must be taken when applying functions to both sides of an inequality.
1/2 > 1/3 . . . 2 < 3 (reciprocal function applied to both sides)
30° < 60° . . . cos(30°) > cos(60°) (cosine function applied to both sides)
if (a + b) = 73 and a b =65 find value of a²+ b²
Step-by-step explanation:
Here,
by formula a^2+b^2=(a+b)^2-2ab
so,
or,(a+b)^2-2ab
or,(73)^2-2×65
or,5329-126
=5203 is the answer
Which inequality is shown in the graph?
I need help plz
Answer:
I am pretty sure it is B.
Step-by-step explanation:
This is a line with a positive slope, therefore we can discard c and d.
the sign < will mean that the shaded in area will be on your right side.
A certain prescription drug diminishes in the system at a rate of 25% per hour. If a person was administered 1450mg of the drug, how much will remain in 4 hours? How many hours will it take for the amount of the drug in their system to be less than 5mg?
9514 1404 393
Answer:
459 mgabout 20 hoursStep-by-step explanation:
The decay factor is 1 -25% = 0.75 per hour, so the exponential equation can be written ...
r(t) = 1450·0.75^t . . . . . milligrams remaining after t hours
__
a) After 4 hours, the amount remaining is ...
r(4) = 1450·0.75^4 ≈ 458.79 . . . mg
About 459 mg will remain after 4 hours.
__
b) To find the time it takes before the amount remaining is less than 5 mg, we need to solve ...
r(t) < 5
1450·0.75^t < 5 . . . . use the function definition
0.75^t < 5/1450 . . . . divide by 1450
t·log(0.75) < log(1/290) . . . . . take logarithms (reduce fraction)
t > log(1/290)/log(0.75) . . . . . divide by the (negative) coefficient of t
t > 19.708
It will take about 20 hours for the amount of the drug remaining to be less than 5 mg.
The population of a strain of bacteria doubles in a culture. At noon there were 80 bacteria present and by 4:00 PM there were 20 480 bacteria. Determine algebraically the doubling period. Hint: You DO NOT need to use systematic trials.
Answer:
t = 1/2 hour
Step-by-step explanation:
20480 = 80[tex]x^{t }[/tex]
20480 = 80[tex]x^{4 }[/tex]
20480/80 = [tex]x^{4 }[/tex]
256 = [tex]x^{4 }[/tex]
x = 4
doubling period
2 = [tex]4^{t}[/tex]
t = 1/2 hour
Find x please explanation need it
Your calculator is showing a result of 248.592.
What is this to the nearest whole number?
I am authoring you to offer free insurance for a year the regular price is 6.99 this will save the customer almost_ a year
Please help due tomorrow
Answer: x= 2.5, y = 10
Step-by-step explanation:
I'm going to assume that these photocopies are proportional in relations to each other.
If they're proportional, you can set up two proportions:
[tex]1) \frac{x}{5} =\frac{3}{6} \\\\2) \frac{5}{y} =\frac{3}{6}[/tex]
And cross-multiply:
[tex]1) 6x = 5*3 \\\\2) 3y = 5*6[/tex]
Then solved for x and y:
[tex]1) 6x = 15\\x=\frac{15}{6} =\frac{5}{2} =2.5 \\\\2) 3y = 30\\y=\frac{30}{3} =10[/tex]
Hari earns Rs 4300 per month. He spends 80% from his income. How much does he save in a year? please give answer in step by step explaination
Answer:
4300 x 12= 51600
20/100 x 51600
10,320 Rs (also pay bohat kam hai :D )
Think of a two-digit number. What is the probability that it has different digits?
Answer:
9/10
Step-by-step explanation:
The first two digit number is 10 and the last is 99. That's a total of 99-10+1 numbers in all. That simplifies to 90. (Just like if we wanted to see how many numbers was 3,4,5, we would do 5-3+1=3 to get the total number.
Anyways, let's consider first how many 2 digjt numbers whose digits are equal. You have 11 22,33,44 55,66,77,88,99 which is 9 numbers total.
So the amount of 2 digits number whose digits differ is 90-9=81.
The probability that a 2 digit number have different digits is 81/90.
This can reduce. Divide top and bottom by 9 giving 9/10.
d) A product contains three lasers, and the product fails if any of the lasers fails. Assume the lasers fail independently. What should the mean life equal for 99% of the products to exceed 10000 hours before failure
Solution :
Let the probability laser works = p
The probability that the system works = [tex]$P(\text{all three component works}) = p^3 $[/tex]
= 0.99
Therefore, p = 0.9967
Now for the above probability critical z = -2.72
Hence, the mean life is equal to = [tex]10,000 + 2.72 \times 600[/tex]
= [tex]10,000+1632[/tex]
[tex]=11,632[/tex]
A function of the form f(x)=ab^x is modified so that the b value remains the same but the a value is increased by 2. How do the domain and range of a new function compare to the domain and range of the original function?
Answer:
The domain and range remain the same.
Step-by-step explanation:
Hi there!
First, we must determine what increasing a by 2 really does to the exponential function.
In f(x)=ab^x, a represents the initial value (y-intercept) of the function while b represents the common ratio for each consecutive value of f(x).
Increasing a by 2 means moving the y-intercept of the function up by 2. If the original function contained the point (0,x), the new function would contain the point (0,x+2).
The domain remains the same; it is still the set of all real x-values. This is true for any exponential function, regardless of any transformations.
The range remains the same as well; for the original function, it would have been [tex]y\neq 0[/tex]. Because increasing a by 2 does not move the entire function up or down, the range remains the same.
I hope this helps!
Which of the following scatterplots do not show a clear relationship and would not have a trend line?
Answer:
the second one
Step-by-step explanation:
it is not going in any general direction
Answer:
B
Step-by-step explanation:
What is the slope of the line that contains these points? xxx 454545 494949 535353 575757 yyy 101010 555 000 -5−5minus, 5 slope:
Answer:
-5/4
Step-by-step explanation:
Given :
x : 45, 49, 53, 57
y : 10, 5, 0, - 5
The slope of the line :
Slope = Rise / Run
y2 = - 5, y1 = 10
x2 = 57, x1 = 45
Rise = y2 - y1 = - 5 - 10 = - 15
Run = x2 - x1 = 57 - 45 = 12
The slope = Rise / Run = - 15 / 12 = - 5/4
Answer:
-1
Step-by-step explanation:
i brought the answer correct
obtain the value of X for which (X+1),(X-5),(X-2) is a geometric progression.hence find the sum of the first 12 terms of the progression.
If x + 1, x - 5, and x - 2 are in a geometric progression, then there is some constant r for which
x - 5 = r (x + 1)
==> r = (x - 5) / (x + 1)
and
x - 2 = r (x - 5)
==> r = (x - 2) / (x - 5)
Then
(x - 5) / (x + 1) = (x - 2) / (x - 5)
Solve for x :
(x - 5)² = (x - 2) (x + 1)
x ² - 10x + 25 = x ² - x - 2
-9x = -27
x = 3
It follows that the ratio between terms is
r = (3 - 5) / (3 + 1) = -2/4 = -1/2
Now, assuming x + 1 = 4 is the first term of the G.P., the n-th term a(n) is given by
a(n) = 4 (-1/2)ⁿ⁻¹
The sum of the first 12 terms - denoted here by S - is then
S = 4 (-1/2)⁰ + 4 (-1/2)¹ + 4 (-1/2)² + … + 4 (-1/2)¹¹
Solve for S :
S = 4 [(-1/2)⁰ + (-1/2)¹ + (-1/2)² + … + (-1/2)¹¹]
(-1/2) S = 4 [(-1/2)¹ + (-1/2)² + (-1/2)³ + … + (-1/2)¹²]
==> S - (-1/2) S = 4 [(-1/2)⁰ - (-1/2)¹²]
==> 3/2 S = 4 (1 - 1/4096)
==> S = 8/3 (1 - 1/4096)
==> S = 1365/512
Question 4 please provide explanation for question
Answer:
A
Step-by-step explanation:
We need to find a equation that is where the domain is all real numbers and the range is all real numbers greater than -3
A square root function cannot equal to all real numbers because we cant take the square root of a negative number. so B and C are already wrong.A cubic function range is all real numbers. so y can be greater than -3 but it would also include. values lesser than -3. so D is Wrong.A is right, the domain of a absolute value function is all real numbers. The range of a absolute value is all numbers greater than or equal to zero but if we subtract 3, it changes into all real numbers greater than or equal to -3
what is x divided by one
Answer:
[tex] x \div 1[/tex]
[tex] = x[/tex]
Answer:
[tex]x\div 1=x[/tex]
Step-by-step explanation:
When x is divided by one it is called reciprocal.
reciprocal is the inverse of a number or a value.
examples: The reciprocal of 3 is 1/3, and the reciprocal of 5 is 1/3.
OAmalOHopeO
How many of 320 million Americans would you predict wear contact lens
Answer:
I think 40 - 60 Million Americans would wear contact lenses.
if( x) means 10 what's (x) divide my 2
Answer:
If you meant that the value of (x) is equal to 10, and you want that value divided by 2, then that would be easy!
10/2 is equal to 5.
If you meant something else, please let me know! :)
Find the length of BC
A. 6.81
B. 7.64
C. 13.37
D. 29.44
Answer:
13.37 = BC
Step-by-step explanation:
Since this is a right triangle, we can use trig functions
cos theta = opp / hyp
cos 27 = BC / 15
15 cos 27 = BC
13.36509 = BC
Rounding to the nearest hundredth
13.37 = BC
Helpekksdjfkfodldkdkdodidididisj Help
Answer:
The answers to your questions are given below.
Step-by-step explanation:
1. m∠1 and m∠2 are complementary. This statement was given from the question.
2. m∠1 + m∠2 = 90°. Complementary angles add up to give 90°.
3. m∠2 = 74°. This was given in the question.
4. m∠1 + 74 = 90°. Since m∠1 and m∠2 are complementary. Their sum will add up to give 90°
5. m∠1 = 16°
We can prove m∠1 = 16° as shown below:
m∠1 + m∠2 = 90° (complementary angles)
m∠2 = 74°
m∠1 + 74 = 90°
Collect like terms
m∠1 = 90 – 74
m∠1 = 16°
