Completed Question
Outputs to be matched to the functions are:
1,2,3,4,51,5,3,2,41, 4, 3, 5, 2 2, 18, 27, 43, 96Answer:
sort(x): 2, 18, 27, 43, 96 order(x): 1, 5, 3, 2, 4 rank(x) : 1, 4, 3, 5, 2none of these : 1, 2, 3, 4, 5Step-by-step explanation:
Given the vector x: x <- c(2, 43, 27, 96, 18)
Sort
In R, the sort(x) function is used to arrange the entries in ascending or descending order. By default, R will sort the vector in ascending order.
Therefore, the output that matches the sort function is:
sort(x): 2, 18, 27, 43, 96
Rank
The rank function returns a vector with the "rank" of each value.
x <- c(2, 43, 27, 96, 18)
2 has a rank of 143 has a rank of 427 has a rank of 396 has a rank of 518 has a rank of 2Therefore, the output of rank(x) is: 1, 4, 3, 5, 2
Order
When the function is sorted, the order function gives the previous location of each of the element of the vector.
Using the sort(x) function, we obtain: 2, 18, 27, 43, 96
In the vector: x <- c(2, 43, 27, 96, 18)
2 was in the 1st position18 was in the 5th position27 was in the 3rd position43 was in the 2nd position96 was in the 4th positionTherefore, the output of order(x) is: 1, 5, 3, 2, 4
Having integrated with respect to ϕ and θ, you now have the constant 4π in front of the integral and are left to deal with ∫[infinity]0A21(e−r/a)2r2dr=A21∫[infinity]0r2(e−r/a)2dr.
What is the value of A21∫[infinity]0r2(e−r/a)2dr?Express your answer in terms of A1 and a.
Find the unique positive value of A1.
Express your answer in terms of a and π.
Answer:
Step-by-step explanation:
[tex]\int\limits^{\infty}_0 {A^2_1} (e^{-r/a})r^2dr= {A^2_1}\int\limits^{\infty}_0r^2(e^{-r/a})^2\, dr)[/tex]
[tex]=A_1^2\int\limits^{\infty}_0 r^2e^{-2r/a}\ dr[/tex]
[tex]=A_1^2[\frac{r^2e^{2r/a}}{-2/a} |_0^{\infty}-\int\limits^{\infty}_0 2r\frac{e^{-2r/a}}{-2/a} \ dr][/tex]
[tex]=A^2_1[0+\int\limits^{\infty}_0 a\ r\ e^{-2r/a}\ dr][/tex]
[tex]=A^2_1[\frac{a \ r \ e^{-2r/a}}{-2/a} |^{\infty}_0-\int\limits^{\infty}_0 \frac{a \ e^{-2r/a}}{-2/a} \ dr][/tex]
[tex]=A_0^2[0-0+\int\limits^{\infty}_0 \frac{a^2}{2} e^{-2r/a}\ dr\\\\=A_1^2\frac{a^2}{2} \int\limits^{\infty}_0 e^{-2r/a}\ dr\\\\=A_1^2\frac{a^2}{2} [\frac{e^{-2r/a}}{-2/a} ]^{\infty}_0[/tex]
[tex]=\frac{A_1^2a^2}{2} -\frac{a}{2} [ \lim_{r \to \infty} [e^{-2r/a} -e^0]\\\\=\frac{A_1^2a^2}{2} -(\frac{a}{2}) (0-1)[/tex]
[tex]=\frac{A_1^2a^3}{4}[/tex]
[tex]\therefore A_1^2\int\limits^{\infty}_0 r^2(e^{-r/a}) \ dr =\frac{A_1^2a^3}{4}[/tex]
Find the unique positive value of A1
[tex]=4\pi (\frac{A_1^2a^3}{4} )\\\\=A_1^2a^3\pi\\\\A_1^2=\frac{1}{a^3\pi} \\\\A_1=\sqrt{\frac{1}{a^3\pi} }[/tex]
Mariah spent $9.50 on 9 pounds of limes and pears. Limes cost $0.50 per pound and pears cost $1.50 per pound. Let l be the number of pounds of limes and let p be the number of pounds of pears.
The system of linear equations that models this scenario is:
l + p = 9
0.5l + 1.5p = 9.5
How many pounds of each type of fruit did she buy?
Answer:
4 pounds of lime and 5 pounds of pears
Step-by-step explanation:
I + P = 9
0.5l + 1.5P = 9.5
I = 9 - P
0.5(9 - P) + 1.5P = 9.5
4.5-0.5P + 1.5P = 9.5
4.5 + P (1P) = 9.5
P = 9.5-4.5 = 5
I = 9 - 5 = 4
Answer: 4 pounds of lime and 5 pounds of pears
Outcome
0
1
5
10
1000
Probability
0.33
0.32
0.24
0.10
0.01
Which is the expected value of the random variable with the given probability distribution?
a.
5.65
c.
12.52
b.
100.44
d.
5
Answer:
The expected value of the random variable with the given probability distribution = 12 .52
Step-by-step explanation:
Given data
x : 0 1 5 10 1000
p(x) : 0.33 0.32 0.24 0.10 0.01
The expected value of the given random variable of given probability distribution
E(X) = ∑ x p ( X = x)
E(X) = 0 × 0.33 + 1 × 0.32 + 5 × 0.24 + 10× 0.10 + 1000×0.01
E (X) = 12.52
What’s the correct answer for this?
Answer:
B. The radius
Step-by-step explanation:
The area of a sector of a circle is ½ r² ∅, where r is the radius and ∅ the angle in radians subtended by the arc at the centre of the circle so we need to know the radius for it
On day two of a study on body temperatures, 106 temperatures were taken. Suppose that we only have the first 10 temperatures to work with. The mean and standard deviation of these 10 temperatures were 98.44oF and 0.30oF, respectively. Construct a 95% confidence interval for the mean of all body temperatures.
Answer:
The 95% confidence interval for the mean of all body temperatures is between 97.76 ºF and 99.12 ºF
Step-by-step explanation:
We have the standard deviation for the sample, so we use the t-distribution 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 = 10 - 1 = 9
95% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 9 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.95}{2} = 0.975[/tex]. So we have T = 2.2622
The margin of error is:
M = T*s = 2.2622*0.3 = 0.68
In which s is the standard deviation of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 98.44 - 0.68 = 97.76 ºF
The upper end of the interval is the sample mean added to M. So it is 98.44 + 0.68 = 99.12 ºF
The 95% confidence interval for the mean of all body temperatures is between 97.76 ºF and 99.12 ºF
A woman forgot her bank ATM PIN but she was able to recall some of the pin.
1)the 1st digit is half of the 2nd pin
2)the sum of 2nd and 3rd is equal to 10
3)the 4th is equal to the 2nd plus 1
4)the sum of all digits is 23
show workings please
what is the ATM digit?
The PIN is 4829
Step-by-step explanation:
let s take 4 numbers a b c and d
the PIN is abcd
we know that
(1) a = b/2
(2) b+c=10
(3) d=b+1
(4) a+b+c+d=23
from (2) c = 10 - b
from (3) d = b + 1
so (4) gives
b/2 + b + 10 - b + b +1 = 23
so
3/2 b = 23 -11 = 12
b = 12*2/3 = 8
so d = 9
c = 10-8=2
and a = 4
so the PIN is 4829
thank you
A real estate purveyor purchases a 60{,}00060,00060, comma, 000 square foot \left(\text{ft}^2\right)(ft 2 )(, start text, f, t, end text, squared, )warehouse and decides to turn it into a storage facility. The warehouse's width is exactly \dfrac 2 3 3 2 start fraction, 2, divided by, 3, end fraction of its length. What is the warehouse's width? Round your answer to the nearest foot.
Answer:
200 feet
Step-by-step explanation:
Area of the warehouse [tex]=60,000$ ft^2[/tex]
Let the length of the warehouse=l
The warehouse's width is exactly [tex]\dfrac23[/tex] of its length
Therefore: Width of the warehouse[tex]=\dfrac23l[/tex]
Area =Length X Width
Therefore:
[tex]\dfrac23l*l=60000\\$Cross multiply\\2l^2=60000*3\\2l^2=180000\\$Divide both sides by 2\\2l^2 \div 2=180000 \div 2\\l^2=90000\\l^2=300^2\\$Length, l=300 feet\\Recall: Width =\dfrac23l\\$Therefore, Width of the warehouse=\dfrac23*300=200$ feet[/tex]
Maria, Daniel, Stephanie, Michael, Elena, Tyler, Sue, and Dimitri have reserved eight seats in a row at the theater, starting at an aisle seat. In how many ways can they arrange themselves if Maria and Daniel are to sit next to each other?
Answer:
1x1x6x5x4x3x2x1 = 720 also they can sit in:
6x1x1x5x4x3x2x1 = 720
6x5x1x1x4x3x2x1 = 720
6x5x4x1x1x3x2x1 = 720
6x5x4x3x1x1x2x1 = 720
6x5x4x3x2x1x1x1 = 720
6x5x4x3x2x1x1x1 = 720 or you could have gone 720 x 7
evaluate will give brainlist
Answer:
C. 1/25
Step-by-step explanation:
5^-2=5^(2*-1)
5^2=25
25^-1=1/25
Answer:
It is C 1/25 because it won't be -25 because a negative times a negative is a positive
Step-by-step explanation:
A boy is playing a ball in a garden surrounded by a wall 2.5 m high and kicks the ball vertically up from a height of 0.4 m with a speed of 14 m/s . For how long is the ball above the height of the wall.
Answer:
2.5 sec
Step-by-step explanation:
Height of wall = 2.5 m
initial speed of ball = 14 m/s
height from which ball is kicked = 0.4 m
we calculate the speed of the ball at the height that matches the wall first
height that matches wall = 2.5 - 0.4 = 2.1 m
using = + 2as
where a = acceleration due to gravity = -9.81 m/s^2 (negative in upwards movement)
= + 2(-9.81 x 2.1)
= 196 - 41.202
= 154.8
v = = 12.44 m/s
this is the velocity of the ball at exactly the point where the wall ends.
At the maximum height, the speed of the ball becomes zero
therefore,
u = 12.44 m/s
v = 0 m/s
a = -9.81 m/s^2
t = ?
using V = U + at
0 = 12.44 - 9.81t
-12.44 = -9.81
t = -12.44/-9.81
t = 1.27 s
the maximum height the ball reaches will be gotten with
= + 2as
a = -9.81 m/s^2
0 = + 2(-9.81s)
0 = 196 - 19.62s
s = -196/-19.62 = 9.99 m. This the maximum height reached by the ball.
height from maximum height to height of ball = 9.99 - 2.5 = 7.49 m
we calculate for the time taken for the ball to travel down this height
a = 9.81 m/s^2 (positive in downwards movement)
u = 0
s = 7.49 m
using s = ut + a
7.49 = (0 x t) + (9.81 x )
7.49 = 0 + 4.9
= 7.49/4.9 = 1.53
t = = 1.23 sec
Total time spent above wall = 1.27 s + 1.23 s = 2.5 sec
Help me please the questions are in the picture!!! THX MARK U AS BRAINIEST
Answer:
D is 10
b/12
Step-by-step explanation:
A candy bag contains 12 green candies and 1 blue candy. Preston will choose 2 candies from the bag without looking. Which answer describes a possible event?
Answer: this is a guess but 7.69 percent chance that you will pick a blue candy
Step-by-step explanation:
Answer:
Choosing 1 blue and 1 green candy
Step-by-step explanation:
There are no red candies and there is only 1 blue candy.
What is the area of the parallelogram With a base of 14 cm and a height of five cm?
Answer:
[tex]70 \: cm^2[/tex]
Step-by-step explanation:
Area of parallelogram.
[tex]A=bh[/tex]
[tex]b \times h[/tex]
[tex]14 \times 5[/tex]
[tex]=70[/tex]
A political analyst believes that a senator's recent decision to support a bill resulted in a drop of approval ratings. To test this claim, he selects random cities in the state that voted the senator in and compares the approval ratings before the decision to the approval ratings after the decision. Suppose that data were collected for a random sample of 8 cities, where each difference is calculated by subtracting the percent approval rating before the decision from the percent approval rating after the decision. Assume that the percentages are normally distributed. What type of test is this hypothesis test?
Answer:
A paired sample t-test
Step-by-step explanation:
A paired sample t-test is most of the time used when in determining the difference between two related dependent variables and in this context; we have
approval ratings before the senator's decision variables and
approval rating after the senator's decision variables for the same subject
These revolves around the senator's decision causing a decrease in approval ratings. Often the two variables are separated by time.
It is used to determine whether the mean of the dependent variable (approval ratings) is the same in the two related groups (the before and after decision groups).
Write an
explicit formula for
ans
the nth
term of the sequence 20, -10,5, ....
Answer:an=20(-1/2)^n-1
Step-by-step explanation:
1 adult and 6 children went swimming. How much did they pay together
Answer:
[tex]x+6y[/tex] where x is the cost of one adult ticket and y is the cost of one child ticket.
Step-by-step explanation:
This is an incomplete question since we would need to know the cost of the adult ticket and the cost of the children ticket.
However, let's say that the price is x dollars per adult and y dollars per child.
Now, we need to find out how much one adult and 6 children paid.
Thus, we would have to multiply the cost per adult by the number of adults and the cost per child per number of children and then sum up these two results.
Writing this in an algebraic way we would have:
[tex]1(x)+6y\\x+6y[/tex]
Thus, 1 adult and 6 children would have paid x + 6y dollars where x is the cost of the adult ticket and y is the cost of the children ticket.
(For example, if an adult ticket is 6 dollars and a child ticket is 4 dollars we would have that they paid 6 + 6(4) = 6 + 24 = 30 dollars)
A student works at an on- campus job Monday through Friday. The student also participates in intramural volleyball on Tuesdays and Thursdays. Given Events A and B, are the two events mutually exclusive? Explain your answer.
Event A: On a random day of the week, the student is working at their on-campus job.
Event B: On a random day of the week, the student is playing intramural volleyball.
Answer:
No, the events are not mutually exclusive because they share the common outcomes of the student working and playing volleyball on certain days.
Step-by-step explanation:
A and B are mutually exclusive events if they cannot occur at the same time. This means that A and B do not share any outcomes and P(A AND B)=0.
In this case, A and B have outcomes in common since the student both works and plays volleyball on Tuesdays and Thursdays. Thus, the events are not mutually exclusive.
Please answer...i always answer... please
Answer:
A) -x + y = 2
B) x + 2y = 4
we add both equations
3 y = 6
y = 2
We put y = 2 into equation B)
x + 2 * 2 = 4
x = 0
***********************************************
A) -2x + y = 6
B) x + y = 0
We multiply B) by 2
B) 2 x + 2 y = 0 then we add A)
A) -2x + y = 6
3y = 6
y = 2
Therefore x = -2
Step-by-step explanation:
if jm = 5x - 8 and lm = 2x - 6, which expression represents jl
Answer:
7x -14 = jl
Step-by-step explanation:
Assuming a straight line
jm+ ml = jl
5x-8 + 2x-6 = jl
Combine like terms
7x -14 = jl
Evie has two sets of blocks of identical size and shape with the colors given. Evie will randomly select on block from each set. What is the probability she will select an orange block and a red block?
set A has 4 orange blocks and 3 yellow blocks.
set B has 5 blue blocks and 2 red blocks.
3/7
2/7
8/49
6/49
Answer:
[tex]\frac{8}{49}[/tex]
Step-by-step explanation:
Orange: [tex]\frac{4}{7}[/tex]
Red: [tex]\frac{2}{7}[/tex]
[tex]\frac{4}{7} *\frac{2}{7} =\frac{8}{49}[/tex]
There is a bag with only red marbles and blue marbles.
The probability of randomly choosing a red marble is
7/10
There are 42 red marbles in the bag and each is equally likely to be chosen.
How many marbles in total must there be?
Answer:
There are 60 marbles in the bag
Step-by-step explanation:
The total number of marbles times the probability of red marbles = number of red marbles
total * 7/10 = 42
Multiply each side by 10/7
total * 7/10 * 10/7 = 42*10/7
total
60
There are 60 marbles in the bag
Find the lengths of g, h, and j. Round answers to the nearest tenth. (marking brainliest for correct)
Answer:
j=13, g=20.8, h=24
Step-by-step explanation:
The overall shape given and the shape within, are both right triangles. With right triangles, you are allowed to use the pythagorean theorem formula ([tex]a^{2} + b^{2} = c^{2}[/tex]) in order to solve for some sides. In this case, that would be j and h. The five in the smaller triangle is represented by b and the 12 is the hypotenuse so it is represented by c. When you plug in those numbers in the pythagorean theorem formula, you will find the value of j to be 13. When looking at this, we see that 12 is the second greatest value in the right triangle values that we just found, so we know the the opposing angle for that one will be 60 degrees. The 5's opposing side is therefore 30 degrees. When subtracting 90 and 30, we get 60, so therefore you can use the 30 60 90 formula to find the sides of the bigger triangle. The 60 degrees represents g. This formula will be [tex]a\sqrt{3}[/tex]. The a is 12 since it is the smallest value. So therefore, g is [tex]12\sqrt{3}[/tex], which is 20.8. Now that we have this side, we can just use the pythagorean theorem formula to find the remaining side. Therefore, h is going to be 24
The strength of paper used in the manufacturing of cardboard boxes (y) is related to percentage of hardwood concentration in the original pulp (x). Under controlled conditions, a pilot plant manufactures 16 samples, each from differential batch of pulp, and measures the tensile strength. Determine if there is significance relationship between x and y.
y = 101, 117, 117, 106, 132, 147, 147, 134, 111, 123, 125, 145, 134, 145, 144, 146.9
x = 1.0, 1.5, 1.5, 1.5, 2.0, 2.0, 2.2, 2.4, 2.5, 2.5, 2.8, 2.8, 3.0, 3.0, 3.2, 3.3
Answer:
At a significance level of 0.05, there is enough evidence to claim that there is a significant relationship between x and y.
P-value = 0.003.
Step-by-step explanation:
If we perform a regression analysis relating x and y, we get the best fitting line with equation:
[tex]y=15.82x+92.9[/tex]
and a correlation coefficient r:
[tex]r=0.693[/tex]
We have to test the hypothesis, where the alternative hypothesis claims that there is a relationship between these two variables, and the null hypothesis claiming there is no relationship (meaning that the correlation is not significantly different from 0).
This can be written as:
[tex]H_0: \rho=0\\\\H_a:\rho\neq0[/tex]
where ρ is the population correlation coefficient for x and y.
The significance level is assumed to be 0.05.
The sample size is n=16.
The degrees of freedom are df=14.
[tex]df=n-2=16-2=14[/tex]
The test statistic can be calculated as:
[tex]t=\dfrac{r\sqrt{n-2}}{\sqrt{1-r^2}}=\dfrac{0.693\sqrt{14}}{\sqrt{1-(0.693)^2}}=\dfrac{2.593}{0.721}=3.597[/tex]
For a test statistic t=2.05 and 14 degrees of freedom, the P-value is calculated as:
[tex]\text{P-value}=2\cdot P(t>3.597)=0.003[/tex]
The P-value (0.003) is smaller than the significance level (0.05), so the effect is significant enough.
The null hypothesis is rejected.
At a significance level of 0.05, there is enough evidence to claim that there is a significant relationship between x and y.
Borachio eats at the same fast food restaurant every day. Suppose the time X between the moment Borachio enters the restaurant and the moment he is served his food is normally distributed with mean 4.2 minutes and standard deviation 1.3 minutes. Find the probability that when he enters the restaurant today it will be at least 5 minutes until he is served.
Answer:
26.94% probability that when he enters the restaurant today it will be at least 5 minutes until he is served.
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore 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 pvalue, we get the probability that the value of the measure is greater than X.
In this question, we have that:
[tex]\mu = 4.2, \sigma = 1.3[/tex]
Find the probability that when he enters the restaurant today it will be at least 5 minutes until he is served.
This is 1 subtracted by the pvalue of Z when X = 5. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{5 - 4.2}{1.3}[/tex]
[tex]Z = 0.615[/tex]
[tex]Z = 0.615[/tex] has a pvalue of 0.7308.
1 - 0.7308 = 0.2694
26.94% probability that when he enters the restaurant today it will be at least 5 minutes until he is served.
Use any method to multiply (-14ab)(a + 3b - 4c).
Answer:
-14a^2b-42ab^2+56abc
Step-by-step explanation:
You can use the FOIL method
multiply the first numbers
then inner
then outer
then last
A company is producing two types of ski goggles. Thirty percent of the production is of type A, and the rest is of type B. Five percent of all type A goggles are returned within 10 days after the sale, whereas only two percent of type B are returned. If a pair of goggles is returned within the first 10 days after the sale, the probability that the goggles returned are of type B is:
Answer:
The required probability is 0.4828.
Step-by-step explanation:
We are given that a company is producing two types of ski goggles. Thirty percent of the production is of type A, and the rest is of type B.
Five percent of all type A goggles are returned within 10 days after the sale, whereas only two percent of type B are returned.
Let the probability that production is of Type A = P(A) = 30%
Probability that production is of Type B = P(B) = 1 - P(A) = 1 - 0.30 = 70%
Also, let R = event that pair of goggles are returned
So, the probability that type A goggles are returned within 10 days after the sale = P(R/A) = 5%
Probability that type B goggles are returned within 10 days after the sale = P(R/B) = 2%
Now, given a pair of goggles is returned within the first 10 days after the sale, the probability that the goggles returned are of type B is given by = P(B/R)
We will use the concept of Bayes' Theorem to calculate the above probability.
So, P(B/R) = [tex]\frac{P(B) \times P(R/B)}{P(A) \times P(R/A)+P(B) \times P(R/B)}[/tex]
= [tex]\frac{0.70 \times 0.02}{0.30 \times 0.05+0.70 \times 0.02}[/tex]
= [tex]\frac{0.014}{0.029}[/tex] = 0.4828
Debby is working on her typing.
• At first, Debby typed at a rate of 80 words per minute
After she took a typing class, she could type 300 more words per hour than she could before the typing class.
How many words per minute could Debby type after taking the typing class?
85
130
220
e
300
Answer:
300/60=5 more words per minute
80+5 = 85 words per minute
or
80 x 60 = 4800 + 300 = 5100
5100 / 60 = 85 words per minute
Hope this helps
Step-by-step explanation:
ASAP! GIVING BRAINLIEST! Please read the question THEN answer CORRECTLY! NO guessing. I say no guessing because people usually guess on my questions.
Answer:
D. It would be less steep
Step-by-step explanation:
The first graph moves at a rate of 5/1 which is a greater fraction than 3/4
The second graph is shallow due to the close points in x and y that are able to be conducted The first Graph rapidly increases at a way higher rate making it VERY steepWhile both are linear the second strays away in terms of plot linesDuraBurn claims that the mean lifetime of its SuperGlo light bulbs is 904 hours. A researcher wants to perform a hypothesis test to determine whether the mean lifetime is actually less than this. A random sample of 10 DuraBurn SuperGlo bulbs exhibited an average lifetime x-805 hours with a standard deviation s 158 hours. Using the hypotheses H0: μ = 904 vs Ha: μ < 904, find the P-value and state your conclusion. Use a significance level of 0.05.
1. P-value 0.039, there is not sufficient evidence to conclude the mean lifetime of its SuperGlo light bulbs is less than 904 hours
2. P-value 0.039, there is sufficient evidence to conclude the mean lifetime of its SuperGlo light bulbs is less than 904 hours.
3. P-value 0.079, there is not sufficient evidence to conclude the mean lifetime of its SuperGlo light bulbs is less than 904 hours.
4. P-value0.079, there is sufficient evidence to conclude the mean lifetime of its SuperGlo light bulbs is less than 904 hours
Answer:
Step-by-step explanation:
We would set up the hypothesis test. This is a test of a single population mean since we are dealing with mean
For the null hypothesis,
H0: μ = 904
For the alternative hypothesis,
Ha: μ < 904
This is a left tailed test
Since the number of samples is small and no population standard deviation is given, the distribution is a student's t.
Since n = 10,
Degrees of freedom, df = n - 1 = 10 - 1 = 9
t = (x - µ)/(s/√n)
Where
x = sample mean = 805
µ = population mean = 904
s = samples standard deviation = 158
t = (805 - 904)/(158/√10) = - 1.98
We would determine the p value using the t test calculator. It becomes
p = 0.039
Since alpha, 0.05 > than the p value, 0.03953, then we would reject the null hypothesis. Therefore, the correct option is:
2. P-value 0.039, there is sufficient evidence to conclude the mean lifetime of its SuperGlo light bulbs is less than 904 hours.
g A cannonball is shot with an initial speed of 62 meters per second at a launch angle of 25 degrees toward a castle wall that is 260 meters away. If the wall is 20 meters tall, how high off the ground will the cannonball hit
Answer:
h = 16.23 m
The cannonball will hit the wall at 16.23m from the ground.
Step-by-step explanation:
Given;
Initial speed v = 62m/s
Angle ∅ = 25°
Horizontal distance d = 260 m
Height of wall y = 20
Resolving the initial speed to vertical and horizontal components;
Horizontal vx = vcos∅ = 62cos25°
Vertical vy = vsin∅ = 62cos25°
The time taken for the cannon ball to reach the wall is;
Time t = horizontal distance/horizontal speed
t = d/vx (since horizontal speed is constant)
t = 260/(62cos25°)
t = 4.627 seconds.
Applying the equation of motion;
The height of the cannonball at time t is;
h = (vy)t - 0.5gt^2
Acceleration due to gravity g = 9.81 m/s
Substituting the given values;
h = 62sin25×4.627 - 0.5×9.81×4.627^2
h = 16.2264134736
h = 16.23 m
The cannonball will hit the wall at 16.23m from the ground.
