Answer:
B. 2/5
Step-by-step explanation:
A simple random sample of 41 men from a normally distributed population results in a standard deviation of 10.7 beats per minute. The normal range of pulse rates of adults is typically given as 60 to 100 beats per minute. If the range rule of thumb is applied to that normal range, the result is a standard deviation of 10 beats per minute. Use the sample results with a 0.10 significance level to test the claim that pulse rates of men have a standard deviation equal to 10 beats per minute. Complete parts(a) through (d) below.
a. Identify the null and alternative hypotheses.
b. Compute the test statistic; χ2 = ___ (Round to three decimal places as needed.)
c. Find the P-value; P-value = ____ (Round to four decimal places as needed.)
d. State the conclusion. (choose one from each ( x, y) set)
(Do not reject, Reject) Upper H0, because the P-value is (greater than, less than, or equal to) the level of significance. There is
(sufficient, insufficient) evidence to warrant rejection of the claim that the standard deviation of men's pulse rates is equal to
10 beats per minute.
Answer:
H0 : σ²=10²
H1 : σ²>10²
χ² = 45.796
Pvalue = 0.2442
Do not reject H0 because Pvalue is greater Than significance level
There is insufficient evidence to warrant rejection of the claim that the standard deviation of men's pulse rates is equal to 10 beats per minute.
Step-by-step explanation:
Given that :
Sample size, n = 41
Sample standard deviation, s = 10.7
Population standard deviation, σ = 10
Significance level, α = 0.10
The Hypothesis :
H0 : σ²=10²
H1 : σ²>10²
Using the χ² test for population variance :
The test statistic, χ² = (n-1)*s²/σ²
χ² = (41 - 1) * 10.7²/ 10²
χ² = (40 * 114.49) / 100
χ² = 4579.6 / 100
χ² = 45.796
The Pvalue ;
df = n - 1 ; 41 - 1 = 40
Pvalue(45.796, 40) = 0.2442
Since Pvalue > α ; WE fail to reject H0
Do not reject H0 because Pvalue is greater Than significance level
There is insufficient evidence to warrant rejection of the claim that the standard deviation of men's pulse rates is equal to 10 beats per minute.
Amelia is calculating the density of soccer balls in a bag. She knows the number of balls in the bag and the volume of the bag. Which of the following formulas can be used to calculate the density of balls in the bag?
Density = volume of bag over number of balls
Volume of shelf = density over number of balls
Density = number of balls over volume of bag
Number of books = density over volume of bag
Answer:
Density = number of balls over volume of bag
The formula that can be used to calculate the density of the balls in the bag is Density = number of balls over volume of bag
What is the formula for density?"[tex]Density=\frac{Mass}{Volume}[/tex]"
What is mass?"It is the measure of the matter inside a body."
For given question,
Amelia knows the number of balls in the bag and the volume of the bag.
She wants to calculate the density of soccer balls in a bag.
Here, mass = the number of balls in the bag
By using the density formula,
[tex]Density=\frac{number~of~balls}{volume~of~the~bag}[/tex]
Therefore, the formula that can be used to calculate the density of the balls in the bag is Density = number of balls over volume of bag
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You need a 75% alcohol solution. On hand, you have a 60 mL of a 55% alcohol mixture. You also have 85% alcohol mixture. How much of the 85% mixture will you need to add to obtain the desired solution?
You will need_____ mL of the 85% solution
60 mL=55% alcohol
?mL=85% alcohol
85×60÷55
=92.727 mL
I think do like this....I'm not sure
Hope this help you
9514 1404 393
Answer:
120 mL
Step-by-step explanation:
Let x represent the amount of 85% solution needed. Then the total amount of alcohol in the mix is ...
0.55(60) +0.85(x) = 0.75(60 +x)
33 + 0.85x = 45 +0.75x . . . . . . . eliminate parentheses
0.85x = 12 +0.75x . . . . . . . . . .subtract 33
0.10x = 12 . . . . . . . . . . . . . . subtract 0.75x
x = 120 . . . . . . . . . . . . . . multiply by 10
You will need 120 mL of the 85% solution.
1. A helicopter is at a position from two VORS (VHF Omnidirectional
Radio Range, an aircraft navigation system operating in the VHF band -
not covered in chapter) as in the diagram shown below. Given the angles
shown, find the third angle.
Helicopter
74.0°
66.0°
VOR
VOR
The position of the helicopter and the two VORs forms a triangle and the third angle formed by these three entities is 40 degrees
The diagram is not shown; however, the question can still be answered.
The given angles are:
[tex]\theta_1 = 74.0^o[/tex]
[tex]\theta_2 = 66.0^o[/tex]
Represent the third angle as [tex]\theta_3[/tex]
The helicopter and the 2 VORs form a triangle.
So, we make use of the following theorem to calculate the third angle
[tex]\theta_1 + \theta_2 + \theta_3= 180^o[/tex] ---- sum of angles in a triangle
Substitute known values
[tex]74.0^o + 66.0^o + \theta_3= 180^o[/tex]
[tex]140.0^o + \theta_3= 180^o[/tex]
Collect like terms
[tex]\theta_3= 180 -140.0^o[/tex]
[tex]\theta_3= 40^o[/tex]
Hence, the third angle is 40 degrees.
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The humidity is currently 56% and falling at a rate of 4 percentage points per hour. (a) Estimate the change in humidity over the next 20 minutes. (Round your answer to one decimal place.) -1.4 Incorrect: Your answer is incorrect. percentage points
Answer:
The change is of -1.3 percentage points.
Step-by-step explanation:
The humidity is currently 56% and falling at a rate of 4 percentage points per hour.
This means that after n hours the humidity is of:
[tex]H(n) = 56 - 4n[/tex]
Estimate the change in humidity over the next 20 minutes.
It currently is 56%.
20 minutes is 20/60 = 1/3 of an hours, so:
[tex]H(\frac{1}{3}) = 56 - 4\frac{1}{3} = 54.7[/tex]
Change:
54.7 - 56 = -1.3
The change is of -1.3 percentage points.
The change in humidity over the next 20 minutes falling at a rate of 4 percentage points per hour is -1.3.
The humidity is currently 56% and falling at a rate of 4 percentage points per hour.
What is the formula used to determine the change in humidity?The change is determined by the small about of humidity changes x to x+h, so the output of x+h is the value of f at x plus the approximate change in f, that is
[tex]\rm f(x+h) =f(x) + f'(x) \times h[/tex]
f(x)= 56%
20 minutes is 20/60 = 1/3 of an hours
So, The change in humidity is
[tex]f'(x) = 4 \times 1/3[/tex]
f'(x) = 1.3
Here, it is falling at the rate of 4% point per hour so we will take it as negative as -1.3.
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State and prove the Cantor Intersection Theorem.
Answer:
Cantor's intersection theorem refers to two closely related theorems in general topology and real analysis, named after Georg Cantor, about intersections of decreasing nested sequences of non-empty compact sets.
You are enrolling swimmers in a study on lung capacity. You want 25% of your sample to be those who compete at 100m or less distances and 50% to be swimmers who compete at 100m-500m distances and 25% to be swimmers who compete at >500m distances. You begin enrolling for your study at 5am at the pool. By 9 AM you have all of your 100-500m swimmers enrolled, and all of your >500m swimmers enrolled. This is an example of what type of sampling method
Answer:
Stratified sampling
Step-by-step explanation:
Samples may be classified as:
Convenient: Sample drawn from a conveniently available pool.
Random: Basically, put all the options into a hat and drawn some of them.
Systematic: Every kth element is taken. For example, you want to survey something on the street, you interview every 5th person, for example.
Cluster: Divides population into groups, called clusters, and each element in the cluster is surveyed.
Stratified: Also divides the population into groups. However, then only some elements of the group are surveyed.
In this question:
People divided by groups, for each group(<100, >100<500, >500), a number(not all) is selected, so stratified sampling.
Add .003, 265.8, 83.04
and 1972
Select the correct answer.
Given the following formula, solve for l.
A.
B.
C.
D.
Answer:
c
Step-by-step explanation:
took the test so i assume its this question
find the quadratic equations whose roots are 3 and -4
Answer:
Hello,
Step-by-step explanation:
(x-3)*(x+4)=0 or x²+x-12=0
Answer:
Step-by-step explanation:
[tex]\displyastyle \Large \boldsymbol{} (x-x_1)(x-x_2) \ \ x_1 \ ; \ x_2 -roots \\\\(x-3)(x-(-4))=(x-3)(x+4)=\boxed{x^2+x-12}[/tex]
A company that makes mobile applications surveyed every 10th customer to learn more about how often customers are using one of the company’s new apps. The table shows the results of the survey.
Feedback Number
use frequently
51
use sparingly
23
do not use
12
What is the predicted percentage of customers who use the new app either frequently or sparingly?
A.
59%
B.
74%
C.
85%
D.
86%
Answer:
I hope this helps
Step-by-step explanation:
if x+y=2 and x=4 then x+2y
The graph below displays a fire department’s response time, which measures the time from when the alarm is sounded at the firehouse to the time the first fire engine leaves the station.
A histogram titled Fire Department Response Times has response time (seconds) on the x-axis and relative frequency on the y-axis. 20 to 30, 0.07; 30 to 40, 0.08; 40 to 50, 0.2; 50 to 60, 0.32; 60 to 70, 0.18; 70 to 80, 0.13; 80 to 90, 0.04.
Which interval accounts for the lowest percentage of response times?
20–30 seconds
30–40 seconds
70–80 seconds
80–90 seconds
I think its (D), 80-90 seconds. Someone check me.
Answer:
I also think this is D.
Step-by-step explanation:
This question isn't asking for a lot of math so.
According to the graph, the 80-90 seconds response times are the shortest, meaning it is the least frequent or common.
Plus, it would be a bad thing if it was average anyways, and is outlined by the histogram.
ANSWER NOW IM TIMED Louie uses 10 feet of wood, 16 wheels and one can of paint for every 4 skateboards he builds.
A 4-column table with 3 rows. Column 1 is labeled Skateboards with entries 1, 4, 10. Column 2 is labeled Wood with entries blank, 10 feet, blank. Column 3 is labeled Wheels with entries blank, 16, blank. Column 4 is labeled paint with entries blank, 1 can, blank.
Use the table to find how much of each item Louie needs to build 10 skateboards.
Louie needs
feet of wood,
wheels, and
cans of paint.
Answer: 25 feet of wood
40 wheels and 2.5 cans of paints
Step-by-step explanation:
Answer:
25 feet of wood
40 wheels and
2.5 cans of paints
Step-by-step explanation: I did this before Also can i get brainlyist please
Find the numerical value of the area under the normal curve given the following information:
to the right of z = 2.28
enter your answer as a decimal (NOT percentage) and lead with a zero...for example: 0.1234
Answer:
1 - 0.9887 = 0.0113
Step-by-step explanation:
on a recent algebra test the highest grade was 36 points more then the lowest grade. the sum of the two grades was 132. find the lowest grade.
what is the circumference of a circle with 60 in. as the radius
Answer:
60π
Step-by-step explanation:
circumference of a circle = 2πr, where r = radius
given r = 60 in
2πr = 2×π×60
= 60π
= 188.5 (rounded to the nearest tenth)
a motercycle can travel 60 miles per gallon. approximently how many gallons of fuel will the motercycle need to travel 40 km
[1 mile = 1.6km]
a: 0.04
b: 0.08
c: 0.20
d: 0.42
Answer:
D. 0.42
Step-by-step explanation:
First, convert 40 km to miles by dividing it by 1.6:
40/1.6
= 25
Create a proportion where x is the number of gallons the motorcycle will need to travel 40 km (25 miles):
[tex]\frac{60}{1}[/tex] = [tex]\frac{25}{x}[/tex]
60x = 25
x = 0.4166
Round this to the nearest hundredth:
x = 0.42
So, to travel 40 km, the motorcycle will need 0.42 gallons of fuel.
The correct answer is D. 0.42
Set up and evaluate the integral that gives the volume of the solid formed by revolving the region bounded by y=x^8 and y = 256 in the first quadrant about the y-axis.
Using the shell method, the volume integral would be
[tex]\displaystyle 2\pi \int_0^2 x(256-x^8)\,\mathrm dx[/tex]
That is, each shell has a radius of x (the distance from a given x in the interval [0, 2] to the axis of revolution, x = 0) and a height equal to the difference between the boundary curves y = x ⁸ and y = 256. Each shell contributes an infinitesimal volume of 2π (radius) (height) (thickness), so the total volume of the overall solid would be obtained by integrating over [0, 2].
The volume itself would be
[tex]\displaystyle 2\pi \int_0^2 x(256-x^8)\,\mathrm dx = 2\pi \left(128x^2-\frac1{10}x^{10}\right)\bigg|_{x=0}^{x=2} = \boxed{\frac{4096\pi}5}[/tex]
Using the disk method, the integral for volume would be
[tex]\displaystyle \pi \int_0^{256} \left(\sqrt[8]{y}\right)^2\,\mathrm dy = \pi \int_0^{256} \sqrt[4]{y}\,\mathrm dy[/tex]
where each disk would have a radius of x = ⁸√y (which comes from solving y = x ⁸ for x) and an infinitesimal height, such that each disk contributes an infinitesimal volume of π (radius)² (height). You would end up with the same volume, 4096π/5.
The volume of the solid formed by revolving the region bounded by y=x^8 and y = 256 in the first quadrant about the y-axis is 4096π/5 cubic units.
What is integration?It is defined as the mathematical calculation by which we can sum up all the smaller parts into a unit.
We have a function:
[tex]\rm y = x^8[/tex] or
[tex]x = \sqrt[8]{y}[/tex]
And y = 256
By using the vertical axis of rotation method to evaluate the volume of the solid formed by revolving the region bounded by the curves.
[tex]\rm V = \pi \int\limits^a_b {x^2} \, dy[/tex]
Here a = 256, b = 0, and [tex]x = \sqrt[8]{y}[/tex]
[tex]\rm V = \pi \int\limits^{256}_0 {(\sqrt[8]{y}^2) } \, dy[/tex]
After solving definite integration, we will get:
[tex]\rm V = \pi(\frac{4096}{5} )[/tex] or
[tex]\rm V =\frac{4096}{5}\pi[/tex] cubic unit
Thus, the volume of the solid formed by revolving the region bounded by y=x^8 and y = 256 in the first quadrant about the y-axis is 4096π/5 cubic units.
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a jet flew 2660 miles in 4.75 hours. what is the rate of speed in miles per hour? (the proportion would be 2660:4.75::x:1 set the proportion in fractional form and proceed to fin
Answer: It travels 560 miles per hour.
Step-by-step explanation:
using the proportion,
2660:4.75:x:1
or, 2660:4.75= x:1
or, 2660/4.75 = x/1
or, 2660 = 4.75x
or, x = 2660/4.75
so, x = 560
Answer:
Step-by-step explanation:
Bonjour,
4,75 h = 4+0,75*60 =
4h 45mn = 4*60 + 45 =240+45 => 265mn
265mn -> 2660 miles
1 mn -> 2660/265
60 mn -> (2660*60)/265=> 602,26miles/h
write your answer as an integer or as a decimal rounded to the nearest tenth.
Answer:
6.43
Step-by-step explanation:
Cosine: cos(θ) = Adjacent / Hypotenuse
cosine of 39 degrees = 5/x
.77714596145 = 5/x
x = 5/.77714596145
x= 6.43379782952
Paul can install a 300-square-foot hardwood floor in 18 hours. Matt can install the same floor in 22 hours. How long would it take Paul and Matt to install the floor working together?
4 hours
9.9 hours
13.2 hours
30 hours
Answer:
9.9 hours
Step-by-step explanation:
The formula to determine the time together is
1/a+1/b = 1/c where a and b are the times alone and c is the time together
1/18 + 1/22 = 1/c
The least common multiply of the denominators is 198c
198c(1/18 + 1/22 = 1/c)
11c+ 9c = 198
20c = 198
Divide by 20
20c/20 =198/20
c =9.9
Answer:
B - 9.9 hrs
Step-by-step explanation:
took the test.
Find the answer for x and y
Answer:
x = 57
y = 57
Step-by-step explanation:
because of the two parallel lines :
41+y+8+74 = 180 add like terms
y + 123 = 180 subtract 123 from both sides
y = 57
x - 3 + 41 + y + 8 = 180 because they make a straight line
x + y + 46 = 180
x + 57 + 46 = 180
x + 123 = 180 subtract 123 from both sides
x = 57
What type of function is represented by the following table?
Number of weeks
1 2 3 4 5
Cost of rental car 79,
158,
237,
316,
395
Answer:
Linear
Step-by-step explanation:
cost = 79 * weeks
79*1=79
79*2=158
etc.
Write an equation that has the zero's x={−1,−6}
Answer:
Step-by-step explanation:
If a zero is x = -1, then the factor, going one step backwards, is (x + 1) = 0; if the other zero is x = -6, then the factor is (x + 6) = 0. Now, going backwards one step further, we FOIL those out:
(x + 1)(x + 6) to get x-squared + 6x + 1x + 6 which combines to
[tex]x^2+7x+6=y[/tex]
FOILing those factors together is the opposite of factoring. Factoring gets you the factors, while FOILing puts them back together in the original equation.
A speed training service wants to explore the effectiveness of some of the classes offered to their clients. They randomly select 300 high school athletes and record their 50-meter dash time. The 300 high school athletes are then randomly assigned to three groups with 100 in each. One hundred athletes will take a circuit training class, 100 athletes will take an interval training class, and 100 athletes will take a plyometrics training class. At the end of 10 weeks of taking these classes, their 50-meter dash time will be recorded a second time. Their times will be analyzed to see which class showed the greatest overall improvement in times.
Select all the sentences that correctly identify the components of the experiment.
The experimental units are subjects.
The subjects are the 50 athletes.
There is one treatment, the 50-meter dash.
There are three treatments.
One treatment is a circuit training class.
The factor is the type of class.
There are 10 levels of the factor.
Answer:
A,D,E,F
1,4.5,6
The experimental units are subjects.
There are three treatments.
One treatment is a circuit training class.
The factor is the type of class.
ED2021
2^17+2^14 chia hết cho 9
Step-by-step explanation:
không khó lắm đâu ._.._.._.
There are 36 tables and 7 booths in the family restaurant. Each table seats 4 people. If the restaurant can seat up to 179 people, what is the capacity of each booth?
4 people
5 people
6 people
7 people
Answer:
5 people.
Step-by-step explanation:
First we need to find how many people 36 tables seats. In order to do this, we need to multiply 36 (tables) by 4 (people sitting) to get 144. Now just subtract 144 from 179 to see how many people are left, here we get 35. Since there are 7 booths, we divide 35 by 7 to get 5. Each booth holds 5 people.
(179-36x4)/7=5
Which phrase describes an unknown or changeable quality?
3 feet and 7 inches
4 quarts in a gallon
2 o'clock in the afternoon
The height of the building times 1/2
Answer:
it should be the height of the building time 1/2
Step-by-step explanation:
let me know if its correct or incorrect we'll I hope this help you
(B) An airline knows from experience that the distribution of the number of suitcases that get lost each week on a certain route is normal with μ (mean) = 15.5 and σ (standard deviation) = 3.6. What is the probability that during a given week the airline will lose between 11 and 19 suitcases?
Answer:
The correct answer is "0.7289".
Step-by-step explanation:
The given values are:
Mean,
[tex]\mu = 15.5[/tex]
Standard deviation,
[tex]\sigma = 3.6[/tex]
As we know,
⇒ [tex]z = \frac{(x - \mu)}{\sigma}[/tex]
The probability will be:
⇒ [tex]P(11< x< 19) = P(\frac{11-15.5}{3.6} <z<\frac{19-15.5}{3.6})[/tex]
[tex]=P(z< 0.9722)-P(z< -1.25)[/tex]
By using the z table, we get
[tex]=0.8345-0.1056[/tex]
[tex]=0.7289[/tex]