Answer:
It is, indeed, a reduction. But, the scale factor of the dilation should be a fraction instead of a whole number, since the shape has shrunk.
Instead of [tex]\frac{KN}{K'N'}[/tex], it should be [tex]\frac{K'N'}{KN}[/tex]. That would make it (4 - 2) / (8 - 4) = 2 / 4 = 1/2.
Hope this helps!
Scores on a college entrance examination are normally distributed with a mean of 500 and a standard deviation of 100. What percent of people who write this exam obtain scores between 350 and 650?
Answer:
The percentage is [tex]P(350 < X 650 ) = 86.6\%[/tex]
Step-by-step explanation:
From the question we are told that
The population mean is [tex]\mu = 500[/tex]
The standard deviation is [tex]\sigma = 100[/tex]
The percent of people who write this exam obtain scores between 350 and 650
[tex]P(350 < X 650 ) = P(\frac{ 350 - 500}{ 100} <\frac{ X - \mu }{ \sigma } < \frac{650 - 500}{ 100} )[/tex]
Generally
[tex]\frac{X - \mu }{\sigma } = Z (The \ standardized \ value \ of \ X )[/tex]
[tex]P(350 < X 650 ) = P(\frac{ 350 - 500}{ 100} <Z < \frac{650 - 500}{ 100} )[/tex]
[tex]P(350 < X 650 ) = P(-1.5<Z < 1.5 )[/tex]
[tex]P(350 < X 650 ) = P(Z < 1.5) - P(Z < -1.5)[/tex]
From the z-table [tex]P(Z < -1.5 ) = 0.066807[/tex]
and [tex]P(Z < 1.5 ) = 0.93319[/tex]
=> [tex]P(350 < X 650 ) = 0.93319 - 0.066807[/tex]
=> [tex]P(350 < X 650 ) = 0.866[/tex]
Therefore the percentage is [tex]P(350 < X 650 ) = 86.6\%[/tex]
Kathleen ordered a box of different colored light bulbs to use for stage lighting at the concert. Of the 60 bulbs in the box, 20% were red, 30% were orange, 30% were green, and 20% were blue. Of the blue ones, approximately 10% were damaged. What is the closest estimate for the number of blue bulbs that were damaged?
Answer:
1 bulb
Step-by-step explanation:
First find the number of blue bulbs
60 * 20 %
60 * .2
12 blue bulbs
10 % of the blue were damaged
12 * 10%
12 * .10
1.2
Rounding to the nearest whole number
1 bulb
Which of the following expressions represents a function? (5 points) a {(1, 2), (4, −2), (8, 3), (9, −3)} b y2 = 16 − x2 c 2x2 + y2 = 5 d x = 7
Answer: Option "a" is the only expression that represents a function.
Step-by-step explanation:
A function f(x) = y is a "operator" that takes an input element, x, and assigns it to only one output element, y.
So, if we have that for a given value of x.
f(x) = y and f(x) = h
where y and h are different values, then this is not a function, because is assigning the input value x to two different output values.
Let's see the different options:
a) {(1, 2), (4, −2), (8, 3), (9, −3)}
This points are of the form (x, y)
We can see that each value of x is assigned to only one value of y, so this can represent a function.
b) y^2 = 16 − x^2
Ok, suppose that x = 0, then:
y^2 = 16 - 0 = 16
then we have that y*y = 16.
So y can take two different values:
y = 4 ---> 4*4 = 16
y = -4 ---> -4*-4 = 16.
So this is not a function.
c) 2x^2 + y^2 = 5
First, we want to isolate y in one side:
y^2 = 5 - 2*x^2
Here we have a similar case to the option b, and we can use a similar argument to prove that this is not a function, so we can discard this.
d) x = 7.
Ok, this is not a relation between two variables, so this is not a function, as if x is the input value, we have only one value of x that solves the equation.
what is the end point of a ray
Answer:
point A is the rays endpoint
Step-by-step explanation:
Answer:
The "endpoint" of a ray is the origin point of the ray, or the point at which the ray starts.
Step-by-step explanation:
A ray starts at a given point, the endpoint, and then goes in a certain direction forever ad infinitum. The origin point of a ray is called "the endpoint".
Cheers.
The joint density function for a pair of random variables X and Y is given. f(x, y) = Cx(1 + y) if 0 ≤ x ≤ 4, 0 ≤ y ≤ 4 0 otherwise f(x,y) = 0
A) Find the value of the constant C. I already have 1/24.
B) Find P(X < = 1, Y < = 1)
C) Find P(X + Y < = 1).
Answer:
A) C = 1/96
B) P(x<=1, y<=1) = 1/128 or 0.0078125 to 7 places
C) P(x+y<=1) = 5/2305, or 0.0021701 to 7 places
Step-by-step explanation:
f(x,y) = C x (1+y)
A)
To find C, we need to integrate the volume under region bound by
0 <= x <= 4, and
0 <= y <= 4
This volume equals 1.0.
Find integral,
int( int(f(x,y),x=0,4), y = 0,4) = 96C
therefore C = 1/96
or
F(x,y) = x (1+y) / 96 ............................(1)
B)
P(x<=1, y<=1)
Repeat the integral, substitute the appropriate limits,
P = int( int(F(x,y),x=0,1), y = 0,1)
= 1/128 or 0.0078125
P(x<=1, y<=1) = 1/128 or 0.0078125 to 7 places
C)
P(x+y<=1)
From the function, we know that this is going to be less than one half of the probability in (B), closer to 1/4 of the previous.
It will be again a double integral, as follows:
P = int( int(F(x,y),x=0,1-y), y = 0,1)
= 5/2304
= 0.0021701 (to 7 decimals)
P(x+y<=1) = 5/2305, or 0.0021701 to 7 places
the bold answer is incorrect. what is the right answer?
What would be the mass of a cube of tungsten (density of 19.3 g/cm), with sides of
3cm?
Answer:
M= 521.1 g
Step-by-step explanation:
1st. Find the volume of the cube: V=3³=27 cm³
As the weight of V= 1 cm³ cube is 19.3 g the weight of the cube=27 cm³ is
M=27*19.3= 521.1 g
Write down the name of the shape for question D. Please help!
Step-by-step explanation:
thats shape is a delta
:)
Answer:
arrow head
Step-by-step explanation:
The higher the bowling score the better. The lower the golf score the better. Assume both are normally distributed. a. Suppose we have a sample of the Santa Ana Strikers' bowling scores. Q1 = 125 and Q3 = 156. Would it be usual or unusual to have a score of 200?b. Suppose the mean bowling score is 155 with a standard deviation of 16 points. What is the probability that in a sample of 40 bowling scores, the mean will be smaller than 150?c. Suppose the mean golf score is 77 with a standard deviation of 3 strokes We will give a trophy for the best 5% of scores. What score must you get to receive a trophy? d. Suppose the mean golf score is 77 with a standard deviation of 3 strokes. Would a golf score of 70 be ordinary, a mild outlier, or an extreme outlier?
Answer:
Explained below.
Step-by-step explanation:
(a)
The first and third quartiles of bowling scores are as follows:
Q₁ = 125 and Q₃ = 156
Then the inter quartile range will be:
IQR = Q₁ - Q₃
= 156 - 125
= 31
Any value lying outside the range (Q₁ - 1.5×IQR, Q₃ + 1.5×IQR) are considered as unusual.
The range is:
(Q₁ - 1.5×IQR, Q₃ + 1.5×IQR) = (125 - 1.5×31, 156 + 1.5×31)
= (78.5, 202.5)
The bowling score of 200 lies in this range.
Thus, the bowling score of 200 is usual.
(b)
Compute the probability that the mean bowling score will be smaller than 150 as follows:
[tex]P(\bar X<150)=P(\frac{\bar X-\mu}{\sigma/\sqrt{n}}<\frac{150-155}{16/\sqrt{40}})[/tex]
[tex]=P(Z<-1.98)\\=1-P(Z<1.98)\\=1-0.97615\\=0.02385\\\approx 0.024[/tex]
Thus, the probability that in a sample of 40 bowling scores, the mean will be smaller than 150 is 0.024.
(c)
It is provided that, the lower the golf score the better.
So, the best 5% of scores would be the bottom 5%.
That is, P (X > x) = 0.05.
⇒ P (Z > z) = 0.05
⇒ P (Z < z) = 0.95
⇒ z = 1.645
Compute the value of x as follows:
[tex]z=\frac{x-\mu}{\sigma}\\\\1.645=\frac{x-77}{3}\\\\x=77+(3\times 1.645)\\\\x=81.935\\\\x\approx 82[/tex]
Thus, the score is 82.
(d)
A z-scores outside the range (-2, +2) are considered as mild outlier and the z-scores outside the range (-3, +3) are considered as extreme outlier.
Compute the z-score for the golf score of 70 as follows:
[tex]z=\frac{x-\mu}{\sigma}[/tex]
[tex]=\farc{70-77}{3}\\\\=\frac{-7}{3}\\\\=-2.33[/tex]
As the z-score for the golf score of 70 is less than -2, it is considered as a mild outlier.
While you can use the correlation coefficient as its own test statistic, what is the other appropriate test statistic often used to examine the significance of a correlation
Answer:
T-test
Step-by-step explanation:
Significance of correlation between two variables x and y measures the strength and direction of their relationship. This is used to make future forecasts of the behaviour of a variable under study.
Correlation coefficient can be used to measure significance of correlation, but we can also use the t-test.
T-test is a statistics that is inferential. It measures the significance of difference between the means of two groups.
T-test is the statistic of choice when carrying out hypothesis testing.
T distribution values and degrees of freedom are used to determine statistical significance.
For example the means of two samples can be compared to determine of the come from the same population
A planet rotates on an axis through its poles and 1 revolution takes 1 day 1 day is 24 hours. The distance from the axis to a location the planet 30 degrees north latitude is about 3387.5 miles. Therefore, a location on the planet at 30 degrees north latitude is spinning on a circle of radius 3387.5 miles.
Compute the linear speed on the surface of the planet at 30 degrees north latitude.
Answer:
The velocity is [tex]v = 886.96 \ m/s[/tex]
Step-by-step explanation:
From the question we are told that
The period of each revolution is [tex]T = 1\ day = 24 \ hours[/tex]
The angle is [tex]\theta = 30^o[/tex]
The radius is [tex]r = 3387.5 \ miles[/tex]
Generally the linear speed is mathematically represented as
[tex]v = w * r[/tex]
Where [tex]w[/tex] is the angular speed which is mathematically represented as
[tex]w = \frac{2 \pi }{T}[/tex]
substituting values
[tex]w = \frac{2 *3.142 }{24}[/tex]
[tex]w = 0.2618 \ rad/s[/tex]
Thus
[tex]v = 0.261833 * 3387.5[/tex]
[tex]v = 886.96 \ m/s[/tex]
find the value of x - Secant and Tangent Angles in Circles
Answer:
C. 70°
Step-by-step explanation:
The inscribed angle marked 15° intercepts an arc that is double that measure, so the intercepted arc on the right is 2×15° = 30°.
The external angle marked 20° is half the difference of the intercepted arcs, so is ...
20° = (1/2)(x - 30°)
40° = x - 30° . . . . . . multiply by 2
70° = x . . . . . . . . . . . add 30°
The value of x is 70°.
Identify the recursive formula for the sequence given by the explicit formula f(n) = 20 – 4(n − 1).
Answer:
[tex]\huge\boxed{f(n)=\left\{\begin{array}{ccc}f(1)=20\\f(n)=f(n-1)-4\end{array}\right}[/tex]
Step-by-step explanation:
[tex]f(n)=20-4(n-1)=20+(n-1)(-4)\\\\\text{It's an explicit formula of an arithmetic sequence:}\\\\f(n)=a_1+(n-1)(d)\\\\a_1-\text{first term}\\d-\text{common difference}\\\\\text{Conclusion:}\\\text{Next term}=\text{previous one}\ -4\\\\\text{The recursive formula:}\\\\\huge\boxed{f(n)=\left\{\begin{array}{ccc}f(1)=20\\f(n)=f(n-1)-4\end{array}\right}[/tex]
Answer:
Step-by-step explanation:
someone answered already
Find the volume of the solid. When appropriate, use π=3.14 and round your answer to the nearest hundredth.
Answer:
3179.25
Step-by-step explanation:
Hello!
To find the volume of a cylinder we use the equation
[tex]V = \pi r^{2} h[/tex]
V is volume
r is radius
h is height
Put in what we know. It is says to use pi as 3.14
[tex]V = 3.14 * 7.5^{2} *18[/tex]
Solve
V = 3.14 * 56.25 * 18
V = 3179.25
Hope this Helps!
please solve quick
Answer:
x = 5
AC = 6
DC = 8
Step-by-step explanation:
∆ABC ~ ∆CDE
Therefore, [tex] \frac{AB}{ED} = \frac{AC}{DC} [/tex]
AB = 3
ED = 4
AC = x + 1
DC = x + 3
Plug in the values and solve for x:
[tex] \frac{3}{4} = \frac{x + 1}{x + 3} [/tex]
Cross multiply
[tex] 3(x + 3) = 4(x + 1) [/tex]
[tex] 3x + 9 = 4x + 4 [/tex]
[tex] 3x - 4x = -9 + 4 [/tex]
[tex] -x = -5 [/tex]
[tex] x = 5 [/tex]
Plug in the value of x and find AC and DC
AC = x + 1 = 5 + 1 = 6
DC = x + 3 = 5 + 3 = 8
Even though the population standard deviation is unknown, an investigator uses z rather than the more appropriate t to test a hypothesis at the .01 level of significance. In this situation the true level of significance of this test is
Answer:
The true true level of significance of this test is more than 0.01.
Step-by-step explanation:
No standard deviation and we are told that the investigator still used z rather than the more appropriate t - distribution.
This method of using the z-distribution when standard deviation is unknown will definitely result in a smaller critical value and this in turn simply means that the p-value will be smaller than what it should really be.
Thus, it means the critical value is getting closer to the mean value than the way it should be.
Therefore, means that for a given significance of 0.01 and using the z-distribution under this no standard deviation situation, the true true level of significance of this test is more than 0.01.
True or false? "In any sample data set, the sum of all the values is equal to the product of the mean and the sample size."
Answer:
TRUEStep-by-step explanation:
One of the method of analysing the distribution of a dataset is by finding the mean of the dataset which is part of the measure of central of tendency.
Mean of a dataset is also known as the average and it is the ratio of the sum of the individual dataset to the sample size.
Mathematically xbar = ΣXi/N where
ΣXi is the sum of the individual dataset
N is the sample size
xbar is the mean
From the formula, ΣXi = xbar * N
This means that the sum of the individual dataset (all values in the dataset) is equal to the product of the mean (xbar) and the sample size(N).
Hence the statement that In any sample data set, the sum of all the values is equal to the product of the mean and the sample size."is TRUE
Given: AQRS where m2Q = 20° and m2S = 90°
R
1,000 meters
Q
S
What is the length of segment RS?
342 m
364 m
500 m
940 m
Answer:
342 m
Step-by-step explanation:
SIn(20) * 1000 = RS
342 = RS
According to the U.S. Energy Information Administration the average number of televisions per household in the United States was 2.3. A college student claims the average number of TV’s per household in the United States is different. He obtains a random sample of 73 households and finds the mean number of TV’s to be 2.1 with a standard deviation of 0.84. Test the student’s claim at the 0.01 significance level.
Let [tex]\mu[/tex] be the average number of televisions per household in the United States .
As per given ,
[tex]H_0:\mu =2.3\\\\ H_a:\mu\neq2.3[/tex]
Since [tex]H_a[/tex] is two-tailed and population standard deviation is unknown, so the test is two-tailed t-test.
For sample : Sample size : n= 73, sample mean: [tex]\overline{x}[/tex] = 2.1, sample standard deviation : s= 0.84.
[tex]t=\dfrac{\overline{x}-\mu}{\dfrac{s}{\sqrt{n}}}[/tex]
[tex]t=\dfrac{2.1-2.3}{\dfrac{0.84}{\sqrt{73}}}\\\\ t=-2.034[/tex]
T-critical value for degree of freedom n-1 = 73-1=72 and 0.01 significance level is 2.646 . [By students' t-distribution table]
Since, [tex]|2.034|<2.646[/tex] i.e. [tex]|T_{cal}|<|T_{crit}|[/tex]
This means we cannot reject null hypothesis.
We conclude that the average number of televisions per household in the United States is 2.3 at the 0.01 significance level.
Find out the Time Zone for UAE and its neighboring countries. Express them as positive or negative rational numbers with reference to Greenwich Mean Time. Note down the time of few of your daily activities such as breakfast, school time, lunch time, etc. Compare the same time with GMT.anyone please answer this.
Answer:
UAE is in the Gulf Standard Time zone.
It is GMT + 4
Breakfast: 7 am; GMT 3 am
School time 8 am: GMT 4 am
Lunch time: 12:30 pm; GMT 8:30 am
Step-by-step explanation:
UAE is in the Gulf Standard Time zone.
It is GMT + 4
Breakfast: 7 am; GMT 3 am
School time 8 am: GMT 4 am
Lunch time: 12:30 pm; GMT 8:30 am
Choose the best answer to the following question. Explain your reasoning with one or more complete sentences. At 11:00 you place a single bacterium in a bottle, and at 11:01 it divides into 2 bacteria, which at 11:02 divide into 4 bacteria, and so on. How many bacteria will be in the bottle at 11:30?
Answer:
we could work this out by geometric sequence
Step-by-step explanation:
G1=2, G2=4, we have a formula,Gn=G1r^n-1
G2=G1 (r)^1, 4=2r, r=2
G30=G1 (2)^29=1,073,741,824 bacterium
If Q(x)=x2−6x−2, find Q(−4).
Answer:
Q(-4) = 38Step-by-step explanation:
Q(x)=x² − 6x − 2
To find Q(−4) substitute the value of x which is - 4 into Q(x)
That's
Q(-4) = (-4)² - 6(-4) - 2
Q(-4) = 16 + 24 - 2
We have the final answer as
Q(-4) = 38Hope this helps you
I WILL RATE YOUR BRAINLIEST Marius opened a savings account. The sequence {200, 208, 216.30, 225, …} describes the amount of interest he earns each year his account is active. If this pattern continues, how much total interest will Marius have earned by the 30th year the account is active?
Answer:
11,215Step-by-step explanation:
Given the sequence of interest earned by Marius on his savings account as
200, 208, 216.30, 225, …, the sequence of interest forms a geometric sequence since they have a common ratio.
[tex]r =\frac{T_2}{T_1}= \frac{T_3}{T_2}= \frac{T_4}{T_3}\\ r =\frac{208}{200}= \frac{216.30}{208}= \frac{225}{216.30} \approx 1.04[/tex]
To get how much total interest will Marius have earned by the 30th year the account is active, we will find the sum of the first 30 terms of the geometric sequence as shown.
[tex]S_n =\frac{ a(r^n-1)}{r-1} \ for \ r> 1\\ \\\\ n = 30, a = 200, r = 1.04\\S_{30} = \dfrac{ 200(1.04^{30}-1)}{1.04-1}\\\\S_{30} = \dfrac{ 200(3.243-1)}{0.04}\\\\S_{30} = \dfrac{ 200(2.243)}{0.04}\\\\S_{30} = \dfrac{ 448.6}{0.04}]\\\\S_{30} = 11,215[/tex]
Hence total interest that Marius will earn by the 30th year the account is active is 11,215.
the correct answer is
S30= 200(1-1.04^n)/1-1.04
i took the test
marc mixes blue and yelow paint to ,ake green he has 14 cans blue 20 cans of yellow . he wants green color so one day 1 he mixes 4 blue 6 yellow day 2 he mixes 6 can blue 9 yellowwhats the highest number of cans each color marc can mix to mzke the same shade of green on day 3
Answer:
2 c an of blue and 5 can of yellow
Step-by-step explanation:
3x18 = 3 (10+8) is an example of the _________ property of multiplication.
Answer:
3x18 = 3 (10+8) is an example of the commutative property of multiplication
Step-by-step explanation:
Answer: commutative property of multiplication
Step-by-step explanation:
in the diagram, find the values of a and b.
Answer:
m∠a = 67° , m∠b = 42°Step-by-step explanation:
∠a is alternate interior angle to ∠ECD
∠b is alternate interior angle to ∠BCD
so:
If AB || CD then:
m∠a = m∠ECD = 25° + 42° = 67°
m∠b = 42°
Question 15 please and i will mark the brainliest!!! And thank you to whoever answers
Explanation:
We have 4 options for the first choice and 3 options for the next. So there are 4*3 = 12 different combos possible. The tree diagram below shows 12 different paths to pick from. For instance, the right-most path has us pick the number 4 and the color yellow.
Nala can spend no more than $150 per month on gasoline. She has already purchased $60 in gas this month. Which inequality can be used to find the maximum number of fill-ups she can purchase during the rest of the month, assuming each fill-up costs $30? 30n + 60 > 150 30n + 60 150
Answer:
150<60+30n
Step-by-step explanation:
150 is the maximum amount that she can spend on gas. (which is the total)
she already spend $60
each fill up (n) costs 30
Answer:
the answer is B)
Step-by-step explanation:
John can jog twice as fast as he can walk. He was able to jog the first 5 miles to his grandmother's house, but then he tired and walked the remaining 2 miles. If the total trip took 0.9 hours, then what was his average jogging speed?
Step-by-step explanation:
Suppose, John walks with a speed x
Then, John can jog at a speed 2x
[tex]total \: time \: = \frac{total \: distance}{average \: speed} [/tex]
TOTAL TIME
[tex]0.9 = \frac{5}{2x} + \frac{2}{x} [/tex]
Further solving :
x = 5 mph
Average jogging speed (2x) = 10 mph
Answer:
10mph
Step-by-step explanation:
We know that John's total trip is 0.9 hours, so let's try to figure out how much of that time is spent jogging, and how much of it is spent walking.
We can do that by naming the time he takes to jog a mile y.
An equation would be:
5y+2(2y)=0.9
5y+4y=0.9
y=0.1
It takes him 0.1 hours, or 6 minutes to jog a mile.
Since he jogged 5 miles, his jogging time is 0.5 hours, or 30 minutes.
Now,
Let's name the speed he jogs x (miles per hour)
This allows us to set up another equation.
Note that:
Speed=distance/time
His jogging speed is x.
x=5/0.5
x=10
His average jogging speed is 10 miles an hour.
Solve the following system of equations using the elimination method. x – y = 11 2x + y = 19
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▹ Answer
(10, -1)
▹ Step-by-Step Explanation
x - y = 11
2x + y = 19
Sum up the equations:
3x = 30
Divide 3 on both sides:
x = 10
Substitute:
10 - y = 11
y = -1
Solution:
(x, y) (10, -1)
Hope this helps!
CloutAnswers ❁
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