What is the value of x if 2/ 3 - 2 = -4 ?
Answer:
x= -3
Step-by-step explanation:
(2x/3)-2=-4
Add 2 to both sides
2x/3=-2
multiply both sides by 3
2x=-6
divide both sides by 2
x= -3
Answer:
x = -3
Step-by-step explanation:
2x/3 - 2 = -4
Add 2 to both sides.
2x/3 = -2
Multiply both sides by 3/2.
x = -2 * 3/2
x = -3
in a school project you need to provide a blueprint of the schools rectangular playground .the blueprint dimensions of the playground are 23/147 yd x 3/14 yd after reducing them by the factor of 2/147 what are the original dimensions if the playground in yards
Answer:
L = 0.16 yd, W = 0.22 yd
Step-by-step explanation:
Dimensions of play ground 23/147 yd x 3/14 yd
reducing factor 2/147
Let the original length is L.
[tex]L - \frac{2L}{147} = \frac{23}{147}\\\\L\frac{143}{147} = \frac{23}{147}\\\\L=\frac{23}{143} yd[/tex]
L = 0.16 yd
Let the width is W.
[tex]W - \frac{2W}{147} = \frac{3}{14}\\\\W\frac{143}{147} = \frac{3}{14}\\\\W=0.22 yd[/tex]
3. Tell whether each statement is true or false Explain how you know a) LCM (7, 18) - LCM (14.18) b) LCM (5,8) - LCM (10,8) c) The GCF of any two prime numbers is 1 and the number itself.
Step-by-step explanation:
ok for a. the both are 126
and for b. the both are 30
for c. i believe its true
There are 48 students o the school bus, 28 girls and 20 boys. what is the ratio of boys ad girls on the bus ?
Step-by-step explanation:
28:20
Once simplified its 7:5
Use reduction of order to find a second linearly independent solution
(2x+5)y′′−4(x+3)y′+4y=0,x>−52,y1=e2x
Given that exp(2x) is a solution, we assume another solution of the form
y(x) = v(x) exp(2x) = v exp(2x)
with derivatives
y' = v' exp(2x) + 2v exp(2x)
y'' = v'' exp(2x) + 4v' exp(2x) + 4v exp(2x)
Substitute these into the equation:
(2x + 5) (v'' exp(2x) + 4v' exp(2x) + 4v exp(2x)) - 4 (x + 3) (v' exp(2x) + 2v exp(2x)) + 4v exp(2x) = 0
Each term contains a factor of exp(2x) that can be divided out:
(2x + 5) (v'' + 4v' + 4v) - 4 (x + 3) (v' + 2v) + 4v = 0
Expanding and simplifying eliminates the v term:
(2x + 5) v'' + (4x + 8) v' = 0
Substitute w(x) = v'(x) to reduce the order of the equation, and you're left with a linear ODE:
(2x + 5) w' + (4x + 8) w = 0
w' + (4x + 8)/(2x + 5) w = 0
I'll use the integrating factor method. The IF is
µ(x) = exp( ∫ (4x + 8)/(2x + 5) dx ) = exp(2x - log|2x + 5|) = exp(2x)/(2x + 5)
Multiply through the ODE in w by µ :
µw' + µ (4x + 8)/(2x + 5) w = 0
The left side is the derivative of a product:
[µw]' = 0
Integrate both sides:
∫ [µw]' dx = ∫ 0 dx
µw = C
Replace w with v', then integrate to solve for v :
exp(2x)/(2x + 5) v' = C
v' = C (2x + 5) exp(-2x)
∫ v' dx = ∫ C (2x + 5) exp(-2x) dx
v = C₁ (x + 3) exp(-2x) + C₂
Replace v with y exp(-2x) and solve for y :
y exp(-2x) = C₁ (x + 3) exp(-2x) + C₂
y = C₁ (x + 3) + C₂ exp(2x)
It follows that the second fundamental solution is y = x + 3. (The exp(2x) here is already accounted for as the first solution.)
Sam works at a shoe store. He earns $300 every week plus $15 for every pair of shoes that he sells. How many pairs of shoes would he need to sell to make $500 in a week?
Answer:
300 + 15x = 500
15x = 200
x = 200/15
x=13.333
14 pair of shoes
Step-by-step explanation:
what is the formula for triangle
Answer:
BH/2
Step-by-step explanation:
For the area of the triangle, (BH)/2. B=base and H=height
What is the next three-term of the geometric sequence? 60, 30, 15...?
Answer:
7.5
Step-by-step explanation:
it is feometeic progression
r=0.5
If four pounds of potatoes cost $6.00, how much would 10 pounds of potatoes cost.
SHOW ALL YOUR WORK!!!!!
Answer:
10 pounds of potatoes would cost $15.
Step-by-step explanation:
Set up proportion.
4/6=10/x
simplify 4/6 into 2/3,
2/3=10/x
cross product,
2*x=3*10
2x=30
x=30/2
x=15
lemme just add some to the great reply above,
[tex]\begin{array}{ccll} lbs&\$\\ \cline{1-2} 4&6\\ 10&x \end{array}\implies \cfrac{4}{10}=\cfrac{6}{x}\implies 4x = 60\implies x = \cfrac{60}{4}\implies x = 15[/tex]
What is the inverse of function f? f(x)=10/9+11
Answer:
Option D is answer.
Step-by-step explanation:
Hey there!
Given;
f(x) = 10/9 X + 11
Let f(X) be "y".
y = (10/9) X + 11
Interchange "X" and "y".
x = (10/9) y + 11
or, 9x = 10y + 99
or, y = (9x-99)/10
Therefore, f'(X) = (9x-99)/10.
Hope it helps!
Matthew participates in a study that is looking at how confident students at SUNY Albany are. The mean score on the scale is 50. The distribution has a standard deviation of 10 and is normally distributed. Matthew scores a 65. What percentage of people could be expected to score the same as Matthew or higher on this scale?
a) 93.32%
b) 6.68%
c) 0.07%
d) 43.32%
Answer:
b) 6.68%
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.
The mean score on the scale is 50. The distribution has a standard deviation of 10.
This means that [tex]\mu = 50, \sigma = 10[/tex]
Matthew scores a 65. What percentage of people could be expected to score the same as Matthew or higher on this scale?
The proportion is 1 subtracted by the p-value of Z when X = 65. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{65 - 50}{10}[/tex]
[tex]Z = 1.5[/tex]
[tex]Z = 1.5[/tex] has a p-value of 0.9332.
1 - 0.9332 = 0.0668
0.0668*100% = 6.68%
So the correct answer is given by option b.
A public opinion survey is administered to determine how different age groups feel about an increase in the minimum wage. Some of the results are shown in the table below.
For Against No Opinion
21-40 years 20 5
41-60 years 20 20
Over 60 years 55 15 5
The survey showed that 40% of the 21 - 40 year-olds surveyed are against an increase, and 15% of the entire sample surveyed has no opinion. How many 21 - 40 year-olds surveyed are for an increase? How many 41 - 60 year-olds are against an increase?
Answer:
25 ; 35
Step-by-step explanation:
Given :
____________For __ Against __ No Opinion
21-40 years _________20 _______5
41-60 years ___20 ______________20
Over 60 years _55____ 15________ 5
Given that :
40% of 21-40 are against
Then :
40% = 20
To a obtain 100% of 21 - 40
40% = 20
100% = x
Cross multiply
0.4x = 20
x = 20/0.4
x = 50
100% of 21 - 40 = 50 people
For = 50 - (20 + 5)
= 50 - 25
= 25
2.)
Total who have no opinion :
(5 + 20 + 5) = 30
30 = 15%
Total number surveyed will be , x :
30 = 15%
x = 100%
Cross multiply :
0.15x = 30
x = 30/0.15
x = 200
Number of 41 - 60 against an increase, y:
(25 + 20 + 5 + 20 + y + 20 + 55 + 15 + 5) = 200
165 + y = 200
y = 200 - 165
y = 35
There are four different colored balls in a bag. There is equal probability of selecting the red, black, green, or blue ball.What is the expected value of getting a green ball out of 20 experiments with replacement?
Answer:
The expected value is of 5 green balls.
Step-by-step explanation:
For each experiment, there are only two possible outcomes. Either it is a green ball, or it is not. Since there is replacement, the probability of a green ball being taken in an experiment is independent of any other experiments, 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 expected value of the binomial distribution is:
[tex]E(X) = np[/tex]
20 experiments
This means that [tex]n = 20[/tex]
There is equal probability of selecting the red, black, green, or blue ball.
This means that 1 in 4 are green, so [tex]p = \frac{1}{4} = 0.25[/tex]
What is the expected value of getting a green ball out of 20 experiments with replacement?
[tex]E(X) = np = 20*0.25 = 5[/tex]
The expected value is of 5 green balls.
The expected value of getting a green ball out of 20 experiments with replacement is 5.
What is a binomial distribution?The binomial probability distribution of the number of successes in a sequence of n independent experiments is the binomial distribution with parameters n and p.
As it is given that the probability of all the balls coming out of the bag is equal. Therefore, the probability of a green ball coming can be written as,
[tex]\text{Probability of Green Ball} = 0.25[/tex]
Also, we can write the probability of not getting a green ball can also be written as,
[tex]\rm Probability(\text{Not coming Green Ball}) = P(Red\ ball)+P(Black\ ball)+P(Blue\ ball)[/tex]
[tex]=0.25+0.25+0.25\\\\=0.75[/tex]
Now, as there are only two outcomes possible, therefore, the distribution of the probability is a binomial distribution. And we know that the expected value of a binomial distribution is given as,
[tex]\rm Expected\ Value, E(x) = np[/tex]
where n is the number of trials while p represents the probability.
Now, substituting the values, we will get the expected value,
[tex]\rm Expected\ Value, E(Green\ ball) = 20 \times 0.25 = 5[/tex]
Hence, the expected value of getting a green ball out of 20 experiments with replacement is 5.
Learn more about Binomial Distribution:
https://brainly.com/question/12734585
A regression was run to determine whether there is a relationship between hours of tv watched per day(x) and number of sit-ups a person can do (y). The results of the regression are given below. Use this to predict the number of sit-ups a person who watches 11 hours of tv can do
Y=ax+b
A=-1.341
B=32.234
R=-0.896
Answer:
17
Step-by-step explanation:
Given the regression model :
Y=ax+b
x = Hours of TV watched per day
y= number of sit-ups a person can do
A=-1.341
B=32.234
Y = - 1.341x + 32.234
Predict Y, when x = 11
Y = - 1.341(11) + 32.234
Y = −14.751 + 32.234
Y = 17.483
Hence, the person Cann do approximately 17 sit-ups
Use the arithmetic progression formula to find the sum of integers from 75 to 100.75,76,77....99,100.
Answer:
The sum is 2275
Step-by-step explanation:
Given
[tex]75,76,77....99,100[/tex]
Required
The sum
Using arithmetic progression, we have:
[tex]S_n = \frac{n}{2}(T_1 + T_n)[/tex]
Where:
[tex]T_1 = 75[/tex] --- first term
[tex]T_n = 100[/tex] --- last term
[tex]n = T_n - T_1 + 1[/tex]
[tex]n = 100 - 75 + 1 = 26[/tex]
So, we have:
[tex]S_n = \frac{n}{2}(T_1 + T_n)[/tex]
[tex]S_n = \frac{26}{2}*(75 + 100)[/tex]
[tex]S_n = 13*175[/tex]
[tex]S_n = 2275[/tex]
Match the graph with the correct equation.
A. Y-1 = -1/4(x+5)
B. Y+1= -1/4(x+5)
C. Y-1= -4(x+5)
D. Y-1 =-1/4 (x-5)
Answer:
y - 1 = -1/4(x+5)
Step-by-step explanation:
An airplane flies 105 miles in ½ hour. How far can it fly in 1 ¼ hours at the same rate of speed?
Answer:
262.5 miles
Step-by-step explanation:
Correct me if I am wrong
16. Risa wants to order business cards. A print-
ing company determines the cost (C) to
the customer using the following function,
where b the number of boxes of cards and
n= the number of ink colors.
C= $25.60b + $14.00b(n - 1)
If Risa orders 4 boxes of cards printed in 3
colors, how much will the cards cost?
OA. $214.40
OB. $168.00
C. $144.40
OD. $102.40
Answer:
A - $214.40
Step-by-step explanation:
Since b is the number of boxes of cards and n is the number of ink colors, and we're given the number of boxes of cards, and number of ink colors, we plug in:
4= b
and
3 = n
into the given equation to solve for C.
Using the order of operations we start inside our parentheses and work from there:
C= $25.60*4 + $14.00*4(3 - 1)
C= $25.60*4 + $14.00*4(2)
C= $102.40 + $112
C= $214.40
If f(x) = 3 - 4x, find f(1+a)
I am in the need of assistance thank you !
Step-by-step explanation:
f(x) = 3 - 4x
f(1+a)= 3-4(1+a)
=3-4+4a
=4a-1
one strip is cut into 9 equal bars shade 1/3:of strip
hiiksbsjxbxjsoahwjsissnsks
Need answer urgently
Answer:
x = -2; y = 1
Step-by-step explanation:
See picture below.
We are told matrices B is the inverse of matrix A.
The product of a matrix and its inverse is the identity matrix.
Which of the following is the result of the equation below after completing the square and factoring? x^2-4x+2=10
A. (x-2)^2=14
B. (x-2)^2=12
C. (x+2)^2=14
D. (x+2)^2=8
9514 1404 393
Answer:
B. (x-2)^2=12
Step-by-step explanation:
The constant that completes the square is the square of half the coefficient of the x-term. That value is (-4/2)^2 = 4.
There is already a constant of 2 on the left side of the equal sign, so we need to add 2 to both sides to bring that constant value up to 4.
x^2 -4x +2 = 10 . . . . . . . given
x^2 -4x +2 +2 = 10 +2 . . . . complete the square (add 2 to both sides)
(x -2)^2 = 12 . . . . . . . . . write as a square
What is the Value of the expression 1/4(c cubed + d squared) when c = -4 and d = 10
Answer: 9
Step-by-step explanation:
[tex]\frac{1}{4} (c^{3}+d^{2})[/tex]
c = -4d = 10Substitute in the values into the expression:
[tex]\frac{1}{4} ((-4)^{3}+10^{2})\\\\=\frac{1}{4}(-64+100)\\\\=\frac{1}{4}(36)\\\\=\frac{36}{4} =9[/tex]
Life Expectancies In a study of the life expectancy of people in a certain geographic region, the mean age at death was years and the standard deviation was years. If a sample of people from this region is selected, find the probability that the mean life expectancy will be less than years. Round intermediate -value calculations to decimal places and round the final answer to at least decimal places.
Answer:
The probability that the mean life expectancy of the sample is less than X years is the p-value of [tex]Z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex], in which [tex]\mu[/tex] is the mean life expectancy, [tex]\sigma[/tex] is the standard deviation and n is the size of the sample.
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.
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.
We have:
Mean [tex]\mu[/tex], standard deviation [tex]\sigma[/tex].
Sample of size n:
This means that the z-score is now, by the Central Limit Theorem:
[tex]Z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
Find the probability that the mean life expectancy will be less than years.
The probability that the mean life expectancy of the sample is less than X years is the p-value of [tex]Z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex], in which [tex]\mu[/tex] is the mean life expectancy, [tex]\sigma[/tex] is the standard deviation and n is the size of the sample.
NEED HELP
The average amount of money spent for lunch per person in the college cafeteria is $6.75 and the standard deviation is $2.28. Suppose that 18 randomly selected lunch patrons are observed. Assume the distribution of money spent is normal, and round all answers to 4 decimal places where possible.
C. For a single randomly selected lunch patron, find the probability that this
patron's lunch cost is between $7.0039 and $7.8026.
D. For the group of 18 patrons, find the probability that the average lunch cost is between $7.0039 and $7.8026.
Answer:
C.[tex]P(7.0039<x<7.8026)=0.1334[/tex]
D.[tex]P(7.0039<\bar{x}<7.8026)\approx 0.2942[/tex]
Step-by-step explanation:
We are given that
n=18
Mean, [tex]\mu=6.75[/tex]
Standard deviation, [tex]\sigma=2.28[/tex]
c.
[tex]P(7.0039<x<7.8026)=P(\frac{7.0039-6.75}{2.28}<\frac{x-\mu}{\sigma}<\frac{7.8026-6.75}{2.28})[/tex]
[tex]P(7.0039<x<7.8026)=P(0.11<Z<0.46)[/tex]
[tex]P(a<z<b)=P(z<b)-P(z<a)[/tex]
Using the formula
[tex]P(7.0039<x<7.8026)=P(Z<0.46)-P(Z<0.11)[/tex]
[tex]P(7.0039<x<7.8026)=0.67724-0.54380[/tex]
[tex]P(7.0039<x<7.8026)=0.1334[/tex]
D.[tex]P(7.0039<\bar{x}<7.8026)=P(\frac{7.0039-6.75}{2.28/\sqrt{18}}<\frac{x-\mu}{\frac{\sigma}{\sqrt{n}}})<\frac{7.8026-6.75}{2.28/\sqrt{18}})[/tex]
[tex]P(7.0039<\bar{x}<7.8026)=P(0.47<Z<1.96)[/tex]
[tex]P(7.0039<\bar{x}<7.8026)=P(Z<1.96)-P(Z<0.47)[/tex]
[tex]P(7.0039<\bar{x}<7.8026)=0.97500-0.68082[/tex]
[tex]P(7.0039<\bar{x}<7.8026)=0.29418\approx 0.2942[/tex]
if TS is a midsegment of PQR find TS
Answer:
B. 7
Step-by-step explanation:
Recall: according to thee Mid-segment Theorem of a triangle, the Mid-segment of a triangle is half the length of the base of the triangle
Base length of the traingle, RQ = 14 (given)
Mid-segment = TS
Therefore,
TS = ½(RQ)
Plug in the value
TS = ½(14)
TS = 7
What is the measure of angle b
Answer:
51 ?
Step-by-step explanation:
90-39= 51. I hope its correct
Answer:
51 degrees
Step-by-step explanation:
Well if you look at the picture angle b and the 39 degrees angle together must make a 90 degree angle
90-39 is 51 so therefor angle b must be 51 degrees
what is true for f (x) = 4 times 2x
Answer:
f(x) = 8x
Explanation:
4 x 2 =8
At what x value does the function given below have a hole?
f(x)=x+3/x2−9
Answer:
hole at x=-3
Step-by-step explanation:
The hole is the discontinuity that exists after the fraction reduces. (Still doesn't exist for original of course)
The discontinuities for this expression is when the bottom is 0. x^2-9=0 when x=3 or x=-3 since squaring either and then subtracting 9 would lead to 0.
So anyways we have (x+3)/(x^2-9)
= (x+3)/((x-3)(x+3))
Now this equals 1/(x-3) with a hole at x=-3 since the x+3 factor was "cancelled" from the denominator.
Measurement error that is normally distributed with a mean of 0 and a standard deviation of 0.5 gram is added to the true weight of a sample. Then the measurement is rounded to the nearest gram. Suppose that the true weight of a sample is 166.0 grams.
(a) What is the probability that the rounded result is 167 grams?
(b) What is the probability that the rounded result is 167 grams or more?
Answer:
(a)[tex]0.15731[/tex]
(b)0.02275
Step-by-step explanation:
We are given that
Mean=0
Standard deviation=0.5 g
True weight of a sample=166 g
Let X denote the normal random variable with mean =166+0=166
(a)
P(166.5<X<167.5)
=[tex]P(\frac{166.5-166}{0.5}<\frac{X-\mu}{\sigma}<\frac{167.5-166}{0.5})[/tex]
=[tex]P(1<Z<3)[/tex]
=[tex]P(Z<3)-P(Z<1)[/tex]
[tex]=0.99865-0.84134[/tex]
[tex]=0.15731[/tex]
(b)
[tex]P(X>167)=P(Z>\frac{167-166}{0.5})[/tex]
[tex]=P(Z>2)[/tex]
[tex]=1-P(Z<2)[/tex]
[tex]=1-0.97725[/tex]
[tex]=0.02275[/tex]