Answer:
a) 68%
b) 95%.
c) 2.5%
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
Approximately 68% of the measures are within 1 standard deviation of the mean.
Approximately 95% of the measures are within 2 standard deviations of the mean.
Approximately 99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean of 100,000, standard deviation of 10,000.
a. Approximately what percentage of the salaries fall between $90,000 and $110,000?
90,000 = 100,000 - 10,000
110,000 = 100,000 + 10,000
Within 1 standard deviation of the mean, so approximately 68%.
b. Approximately what percentage of the salaries fall between $80,000 and $120,000?
80,000 = 100,000 - 2*10,000
120,000 = 100,000 + 2*10,000
Within 2 standard deviations of the mean, so approximately 95%.
c. Approximately what percentage of the salaries are greater than $120,000?
More than 2 standard deviations above the mean.
Approximately 95% of the measures are within 2 standard deviations of the mean, so approximately 5% are more than 2 standard deviations from the mean.
The normal distribution is symmetric, which means that 2.5% are more then 2 standard deviations below the mean, and 2.5% are more than 2 standard deviations above the mean, which means that 2.5% of the salaries are greater than $120,000.
41:41
How many solutions does this linear system have?
y=-6x+2.
-12x - 2y = -4
O one solution: (0,0)
one solution: (1, -4)
O no solution
O infinite number of solutions
Answer is C
Answer:
Answer: B
Step-by-step explanation:
just solve keep up learning!
PLEASE HELP ME
If f(x) = -3 and g(x) = 4x2 + x = 4, find (f+ g)(x).
ОА
A. 4x2 + x - 1
O B. 6x2 - 7
O 4x
C. 43+ + 2x-1
O D. 4x+3x-7
Answer:
D. 4x² + 3x/2 - 7
General Formulas and Concepts:
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightAlgebra I
Terms/CoefficientsFunctionsFunction NotationStep-by-step explanation:
Step 1: Define
Identify
f(x) = x/2 - 3
g(x) = 4x² + x - 4
(f + g)(x) is f(x) + g(x)
Step 2: Find
Substitute in functions: (f + g)(x) = x/2 - 3 + 4x² + x - 4Combine like terms: (f + g)(x) = 4x² + 3x/2 - 7Answer:
The answer is C.
Step-by-step explanation:
(f+g)(x)= f(x)+g(x).
So that would be x/2-3 + 4x^2+x-4.
If you combine like terms that would be:
4x^2+x/2+x-4-3=
4x^2+3/2x-7
A car traveling 7/10 of a mile per minute will travel _ miles in 10 minutes
Answer:
7 miles
Step-by-step explanation:
* means multiply
7/10 * 10 = 7
A car took 6 minutes to travel between two stations that are 3 miles apart find the average speed of the car in mph
Answer: 30 mph is the answer.
Step-by-step explanation:
s = 3 miles
t = 6 minutes
so,
60 minute = 1 hour
1 minute = 1/60 hour
6 minutes = 1/60 * 6 = 0.1 hour
so
average speed = s/t
= 3/0.1 = 30 mph
when a force of 400N is applied on a body at angle of 60 degree to the horizontal displacement,the body covers a distance of 8m.what is the work done?
Answer:
1600N
Step-by-step explanation:
Force = 400 N
Angle with horizontal = 60°
Displacement in horizontal direction = 8 m
work done formula when angle is included: Force * distance * cos(angle)
400 * 8 * cos(60)
= 400 * 8 * 1/2
= 1600N
CNBC recently reported that the mean annual cost of auto insurance is 1013 dollars. Assume the standard deviation is 284 dollars. You take a simple random sample of 56 auto insurance policies. Find the probability that a single randomly selected value is less than 995 dollars. P(X < 995)
Answer:
P(X < 995) = 0.4761
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.
CNBC recently reported that the mean annual cost of auto insurance is 1013 dollars. Assume the standard deviation is 284 dollars.
This means that [tex]\mu = 1013, \sigma = 284[/tex]
Find the probability that a single randomly selected value is less than 995 dollars.
This is the p-value of Z when X = 995. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{995 - 1013}{284}[/tex]
[tex]Z = -0.06[/tex]
[tex]Z = -0.06[/tex] has a p-value of 0.4761. So
P(X < 995) = 0.4761
Find the area of the figure
Please help :)
9514 1404 393
Answer:
66.5 cm²
Step-by-step explanation:
A horizontal line at the "knee" on the right will divide the figure into a 4 cm by 2 cm rectangle, and a trapezoid with bases 4 cm and 9 cm, and height 11-2 = 9 cm. Then the total area of the figure is ...
A = LW + 1/2(b1 +b2)h
A = (4 cm)(2 cm) + (1/2)(4 cm +9 cm)(9 cm) = 8 cm² +58.5 cm²
A = 66.5 cm² . . . . area of the figure
Laura lives 15 miles east of Kevin’s place. Kevin lives 8 miles south of Michelle’s place. How far does Michelle live from Laura’s place?
17 miles
24 miles
32 miles
36 miles
Answer:
17 miles.
Step-by-step explanation:
Let's define:
North as the positive y-axis
East as the positive x-axis.
We know that Laura lives 15 miles east of Kevin's place.
Kevin lives 8 miles south of Michelle's place.
So, if we define the origin, (0, 0) as Laura's place.
From:
"that Laura lives 15 miles east of Kevin's place."
We have that the location of Kevin's house is 15 miles west from Laura's place, then Kevin's house is at:
(0, 0) + (-15mi, 0) = (-15mi, 0)
From Kevin lives 8 miles south of Michelle's place, we know that Michelle's live 8 miles north of Kevin's place.
Then the location of Michele's house is the location of Kevin's plus (0, 8mi).
Michelle's house is located at:
(-15mi, 0) + (0, 8mi) =(-15mi, 8mi)
Now we want to find the distance between Michelle's house and Laura's house.
Michelle's house is at (-15mi, 8mi)
Laura's house is at (0mi, 0mi)
Remember that the distance between two points (a, b) and (c, d) is given by:
[tex]D = \sqrt{(a - c)^2 + (b - d)^2}[/tex]
Then the distance between (-15mi, 8mi) and (0mi, 0mi) is:
[tex]D = \sqrt{(-15mi - 0mi)^2 + (8mi - 0mi)^2} = 17mi[/tex]
The correct option is the first one, 17 miles.
Write down 4 pairs of integers a and b such that a divided by b is -5
Which one of the following is a better buy: a large pizza with a 14-inch diameter for $13.00 or a medium pizza with a 7-inch diameter for $4.00?
O Large Pizza
Medium Dizz
Please help :)
Answer:
Large pizza is the answer
A textile fiber manufacturer is investigating a new drapery yarn, which the company claims has a mean thread elongation of 12 kilograms with a standard deviation of 0.5 kilograms. The company wishes to test the hypothesis H0: µ = 12 against H1: µ < 12 using a random sample of n = 4 specimens. Calculate the P-value if the observed statistic is Xbar (average) = 11.25. Suppose that the distribution of the sample mean is approximately normal.
Answer:
The p-value of the test is 0.0013.
Step-by-step explanation:
The test statistic is:
[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, [tex]\sigma[/tex] is the standard deviation and n is the size of the sample.
12 is tested at the null hypothesis:
This means that [tex]\mu = 12[/tex]
Standard deviation of 0.5 kilograms.
This means that [tex]\sigma = 0.5[/tex]
Sample of n = 4 specimens. Observed statistic is Xbar (average) = 11.25.
This means that [tex]n = 4, X = 11.25[/tex]
Value of the test statistic:
[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
[tex]z = \frac{11.25 - 12}{\frac{0.5}{\sqrt{4}}}[/tex]
[tex]z = -3[/tex]
P-value:
Probability of finding a sample mean belo 11.25, which is the p-value of z = -3.
Looking at the z-table, z = -3 has a p-value of 0.0013, thus the this is the p-value of the test.
There are twelve shirts in my closet. Five are red, four are blue, and three are green. What is
the probability that I choose a red or blue shirt to wear tomorrow?
O 65%
0 75%
0 80%
60%
58%
Answer:
the probability that I chose red or blue is 75%
75%
If the probability that an event happens is 0.76, what will be the probability that the event will not happen?
Answer:
24% or 0.24
Step-by-step explanation:
100% or 1 minus 76% or 0.76. That makes 24% or 0.24.
To answer the question you should prob just put in 0.24.
1 Find the value of C to that the function probability density function defined as follow, also calculate the man and variance /4
X -1 0 1
f(x) 3c 3c 6c
Answer:
[tex]c = \frac{1}{12}[/tex]
The mean of the distribution is 0.25.
The variance of the distribution is of 0.6875.
Step-by-step explanation:
Probability density function:
For it to be a probability function, the sum of the probabilities must be 1. The probabilities are 3c, 3c and 6c, so:
[tex]3c + 3c + 6c = 1[/tex]
[tex]12c = 1[/tex]
[tex]c = \frac{1}{12}[/tex]
So the probability distribution is:
[tex]P(X = -1) = 3c = 3\frac{1}{12} = \frac{1}{4} = 0.25[/tex]
[tex]P(X = 0) = 3c = 3\frac{1}{12} = \frac{1}{4} = 0.25[/tex]
[tex]P(X = 1) = 6c = 6\frac{1}{12} = \frac{1}{2} = 0.5[/tex]
Mean:
Sum of each outcome multiplied by its probability. So
[tex]E(X) = -1(0.25) + 0(0.25) + 1(0.5) = -0.25 + 0.5 = 0.25[/tex]
The mean of the distribution is 0.25.
Variance:
Sum of the difference squared between each value and the mean, multiplied by its probability. So
[tex]V^2(X) = 0.25(-1-0.25)^2 + 0.25(0 - 0.25)^2 + 0.5(1 - 0.25)^2 = 0.6875[/tex]
The variance of the distribution is of 0.6875.
Screenshot of the question
9514 1404 393
Answer:
x = 1, x = 7
Step-by-step explanation:
You can see from the graph that the x-intercepts of f(x) are ...
0 = f(-3)
0 = f(3)
To find the corresponding values of x for f(x-4), we can solve ...
0 = f(x -4)
x -4 = -3 ⇒ x = 1
x -4 = 3 ⇒ x = 7
The x-intercepts of the function after translation 4 units right are ...
x = 1, x = 7
__
Your sketch will be the same curve moved 4 units to the right. (Add 4 to every x-value shown.)
Ayuda porfavor !!!!!!!!
Answer:
La hipotenusa del triángulo mide 5 metros, el ángulo (a) mide 53,13º y el ángulo (b) mide 36,87º.
Step-by-step explanation:
Dado que del triángulo rectángulo se conocen sus dos catetos, uno mide 4 metros y el otro 3 metros, para hallar su hipotenusa y sus ángulos interiores se deben realizar los siguientes cálculos:
4^2 + 3^2 = X^2
16 + 9 = X^2
√25 = X
5 = X
sen(a) = 4/5
(a) = 53,13º
(b) = 180 - (90º+53,13º)
(b) = 36,87º
Así, la hipotenusa del triángulo mide 5 metros, el ángulo (a) mide 53,13º y el ángulo (b) mide 36,87º.
Norm has $15,000 to deposit. His daughter is a junior in high school and plans to go to college. Recommend the best way for Norm to store his money. Note that the interest rates are expressed on an annual basis.
a.
A four-year CD paying 4.8% interest, with a substantial penalty for early withdrawal
b.
An online savings account offering 2.3% interest
c.
A money market account paying 3.5% interest, renewable for three-month commitments
d.
A checking account with no monthly fees
Answer:
A money market account paying 3.5% interest, renewable for three-month commitments.
About 9% of the population has a particular genetic mutation. 900 people are randomly selected. Find the standard deviation for the number of people with the genetic mutation in such groups of 900.
Answer:
The standard deviation is of 8.586.
Step-by-step explanation:
For each person, there are only two possible outcomes. Either they have a genetic mutation, or they do not. The probability of a person having the mutation is independent of any other person, which means that the binomial probability distribution is used to solve this question.
Binomial probability distribution
Probability of exactly x successes on n repeated trials, with p probability.
The standard deviation of the binomial distribution is:
[tex]\sqrt{V(X)} = \sqrt{np(1-p)}[/tex]
About 9% of the population has a particular genetic mutation.
This means that [tex]p = 0.09[/tex]
900 people are randomly selected.
This means that [tex]n = 900[/tex]
Find the standard deviation for the number of people with the genetic mutation in such groups of 900.
[tex]\sqrt{V(X)} = \sqrt{900*0.09*0.91} = 8.586[/tex]
The standard deviation is of 8.586.
Look at the numbers in the bon
5
9
-11
6
-21
9
-6
-10
20
1
Find four numbers whose sum is 5
The population of retired citizens in Minneapolis is 86700. If the population increases at a rate of 8.9% each year. What will the population of retirees be in 7 years? Write an exponential growth model for the future population P(x) where r is in years: P(x) = What will the population be in 7 years? (Round to nearest person)
Answer:
157,476 people
Step-by-step explanation:
the formula :
P(x) = 86700. (1+ 0.089)^r
for r = 7
=> P(x) = 86700 × (1+ 0.089)^7
= 86700 × (1.089)^7
= 86700 × 1.8163
= 157,476 people
Ryan spent 1/3 of his monthly salary for rent and 1/7 of his monthly salary for his utility bill. If $759 was left, what was his monthly salary?
Step-by-step explanation:
Given Information :Ryan spent 1/3 of his monthly salary for rent and 1/7 of his monthly salary for his utility bill. Remaining money = $759To calculate :His monthly salary.Calculation :Let us assume his monthly salary as x. According to the question,
➝ Money spent on rent + Money spent for utility bill + Remaining money = His salary
[tex]\longrightarrow\sf {\dfrac{1}{3}x + \dfrac{1}{7}x + 759 = x} \\ [/tex]
[tex]\longrightarrow\sf {\dfrac{7x + 3x + 15939}{21}= x} \\ [/tex]
[tex]\longrightarrow\sf {\dfrac{10x+ 15939}{21}= x} \\ [/tex]
[tex]\longrightarrow\sf {10x+ 15939= 21x} \\ [/tex]
[tex]\longrightarrow\sf {15939= 21x - 10x} \\ [/tex]
[tex]\longrightarrow\sf {15939= 11x} \\ [/tex]
[tex]\longrightarrow\sf {\cancel{\dfrac{15939}{11}}= x} \\ [/tex]
[tex]\longrightarrow\underline{\boxed{\bf {1449= x}}} \\ [/tex]
Therefore, his monthly income is $1449.
calculate and find the area of the figure below 10m 8m 8m 2m 2m 2m 2m 2m
Answer:
can you be more specific?
Step-by-step explanation:
Suppose that the walking step lengths of adult males are normally distributed with a mean of 2.5 feet and a standard deviation of 0.4 feet. A sample of 45 men’s step lengths is taken. Step 1 of 2 : Find the probability that an individual man’s step length is less than 1.9 feet. Round your answer to 4 decimal places, if necessary.
Answer:
0.0668 = 6.68% probability that an individual man’s step length is less than 1.9 feet.
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.
Normally distributed with a mean of 2.5 feet and a standard deviation of 0.4 feet.
This means that [tex]\mu = 2.5, \sigma = 0.4[/tex]
Find the probability that an individual man’s step length is less than 1.9 feet.
This is the p-value of Z when X = 1.9. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{1.9 - 2.5}{0.4}[/tex]
[tex]Z = -1.5[/tex]
[tex]Z = -1.5[/tex] has a p-value of 0.0668
0.0668 = 6.68% probability that an individual man’s step length is less than 1.9 feet.
Show process!!!!!!!
Thank you
======================================================
Work Shown:
We can apply the law of cosines
a^2 = b^2+c^2-2*b*c*cos(A)
(sqrt(5))^2 = (sqrt(2))^2+(3)^2-2*(sqrt(2))*(3)*cos(A)
5 = 2+9-6*(sqrt(2))*cos(A)
5 = 11-6*(sqrt(2))*cos(A)
11-6*(sqrt(2))*cos(A) = 5
-6*(sqrt(2))*cos(A) = 5-11
-6*(sqrt(2))*cos(A) = -6
(sqrt(2))*cos(A) = -6/(-6)
(sqrt(2))*cos(A) = 1
cos(A) = 1/(sqrt(2))
cos(A) = sqrt(2)/2
A = 45 degrees
Use the unit circle for the last step.
Interestingly, this triangle has only one angle that is a whole number. The other two angles are approximate decimal values.
6. Lerato wants to purchase a house
that costs R 850 000. She is required to
pay a 12% deposit and she will borrow
the balance from a bank. Calculate
the amount that Lerato must borrow
from the bank.
Answer:
J
Step-by-step explanation:
Answer: 748,000
Step-by-step explanation: Multiply 850,000 by 0.12 and you would get 102,000 then you would subract 102,000 from 850,000 getting 748,000
i’ll give brainliest to the right answer plz help
9514 1404 393
Answer:
water
Step-by-step explanation:
Comparison of numbers can be done a couple of different ways. One way is to subtract one from the other. If the difference is positive, the minuend (first number) is the larger of the two.
Another way is to divide one number by the other. If the ratio is more than 1, then the numerator is the larger number.
For numbers in scientific notation, the division is perhaps the easiest. Here, that gives you ...
[tex]\displaystyle\frac{\text{water mass}}{\text{oxygen mass}}=\frac{2.99\times10^{-26}\text{ kg}}{2.66\times10^{-26}\text{ kg}}=\frac{2.99}{2.66}\approx 1.12[/tex]
This value is greater than 1, so the mass of a water molecule is greater.
__
You will note that the multipliers (10^-26 kg) cancelled because they were equal. If they are unequal, the usual rules of exponents apply.
What are the coordinates of the terminal point for 8 = 330°?
1
A.
-
I
22
1
V3
O B.
2
V3
1
O c.
2
D.
1 3
2 2
Answer:
Step-by-step explanation:
If you plot this angle in the coordinate plane, you will find yourself in the fourth quadrant with a referencew angle of 30. Constructing the triangle from that reference angle and using the Pythagorean triple for a 30-60-90 triangle, you get that the side adjacent to the reference angle is √3, the side opposite the reference angle is a -1, and the hypotenuse (which is NEVER negative!) is 2. The x and y coordinates of the terminal point result from the cos (related to the x coordinate) and the sin (related to the y coordinate). The cos of 30:
[tex]cos(30)=\frac{\sqrt{3} }{2}[/tex] and the sin of 30:
[tex]sin(30)=-\frac{1}{2}[/tex] so the coordinates of the terminal point on that angle are
[tex](\frac{\sqrt{3} }{2},-\frac{1}{2})[/tex]
You could also just go to your unit circle, find the angle 330 and look at the coordiantes they give you there for (cos, sin). But I'm a high school math teacher so I wanted you to know how to find this outside of the unti circle. Cuz what if you lost it!?
The graph below represents the distance of a dog from a trainer after a command is given.
Which statement could describe the dog’s movement 5 seconds after the command was given?
The dog stopped to lie down and obey the trainer’s command.
The dog was running towards the trainer to receive a treat.
The dog was running away from the trainer to chase a squirrel.
The dog was stopped but began running towards the trainer.
Answer:
.
Step-by-step explanation:
In a random sample of 26 residents of the state of Montana, the mean waste recycled per person per day was 2.8 pounds with a standard deviation of 0.23 pounds. Determine the 80% confidence interval for the mean waste recycled per person per day for the population of Montana. Assume the population is approximately normal. Step 1 of 2: Find the critical value that should be used in constructing the confidence interval. Round your answer to three decimal places.
Answer:
The critical value that should be used in constructing the confidence interval is T = 1.316.
The 80% confidence interval for the mean waste recycled per person per day for the population of Montana is between 2.741 pounds and 2.859 pounds.
Step-by-step explanation:
We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 26 - 1 = 25
80% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 25 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.8}{2} = 0.9[/tex]. So we have T = 1.316
The critical value that should be used in constructing the confidence interval is T = 1.316.
The margin of error is:
[tex]M = T\frac{s}{\sqrt{n}} = 1.316\frac{0.23}{\sqrt{26}} = 0.059[/tex]
In which s is the standard deviation of the sample and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 2.8 - 0.059 = 2.741 pounds
The upper end of the interval is the sample mean added to M. So it is 2.8 + 0.059 = 2.859 pounds.
The 80% confidence interval for the mean waste recycled per person per day for the population of Montana is between 2.741 pounds and 2.859 pounds.
A senior class of 420 students will rent buses and vans for a class trip. Each bus can transport 50 students and 3 chaperones and costs $1200 to rent. Each van can transport 10 students and 1 chaperone and costs $100 to rent. There are 36 chaperones available (so they can't all go in vans). How many vehicles of each type should be rented in order to minimize the cost
Answer:
37 buses and 1 van.
Step-by-step explanation:
The cost to rent a van is $1200 for 50 students and 3 chaperones, while a bus for 10 students and a chaperone is $100 .
The cost of renting buses for 50 students is $500
What we do is rent 37 buses and 1 van
37 buses will take in 370 students with empty 2 spaces in 2 buses for chaperones since the chaperones are 36.
Then rent 1 van to take in 50 students and 1 chaperone.
The total cost here will be
$3700 + $1200 = $ 4900
This will help to safe cost.