PLEASE HELP ME W THIS
9514 1404 393
Answer:
(b) C = dπ
Step-by-step explanation:
The irrational value π is the ratio between the circumference of a circle and its diameter. That is ...
π = C/d
Rearranging to get a formula for the circumference, we have ...
C = dπ
pls help will give brainliest and only put 1 variable in it ty
Answer:
(2/3)r=30
r=45cm
Step-by-step explanation:
When trying to find a fraction of something, multiply to get your answer:
(2/3) of r = (2/3)r
The blue ribbon can be represented by both 30cm and (2/3)r cm:
(2/3)r=30
2r=90
r=45cm
In selecting a sulfur concrete for roadway construction in regions that experience heavy frost, it is important that the chosen concrete has a low value of ther- mal conductivity in order to minimize subsequent damage due to changing temperatures. Suppose two types of concrete, a graded aggregate and a no-fines aggregate, are being considered for a certain road. The table below summarizes data on thermal conductivity from an experiment carried out to compare the two types of concrete.
Ğ¢ÑÑеп ni xi si
Graded 42 0.486 0.187
No-fines Ñ 42 0.359 0.158
Assume that the conductivity for each sample of concrete is independent of that of all the others. Our interest is in determining if the mean conductivity for the graded concrete is significantly different than the mean conductivity for the no-fines concrete?
Required:
a. Formulate the above in terms of a hypothesis testing problem.
b. Give the test statistic and its reference distribution (under the null hypothesis).
c. Report the p-value of the test statistic and use it to assess the evidence that this sample provides on the scientific question of difference in mean conductivity of the two materials at the 5% level of significance.
Step-by-step explanation:
Given - In selecting a sulfur concrete for roadway construction in regions that experience heavy frost, it is important that the chosen concrete has a low value of thermal conductivity in order to minimize subsequent damage due to changing temperatures. Suppose two types of concrete, a graded aggregate and a no-fines aggregate, are being considered for a certain road. The table below summarizes data on thermal conductivity from an experiment carried out to compare the two types of concrete.
Type ni xi si
Graded 42 0.486 0.187
No-fines 42 0.359 0.158
To find - a. Formulate the above in terms of a hypothesis testing problem.
b. Give the test statistic and its reference distribution (under the null hypothesis).
c. Report the p-value of the test statistic and use it to assess the evidence that this sample provides on the scientific question of difference in mean conductivity of the two materials at the 5% level of significance.
Proof -
a.)
Hypothesis testing problem :
H0 : There is significant difference between mean conductivity for the graded concrete and mean conductivity for the no fines concrete.
H1 : There is no significant difference between mean conductivity for the graded concrete and mean conductivity for the no fines concrete.
b)
Test statistic :
[tex]Z = \frac{x_{1} - x_{2} }{\sqrt{\frac{s_{1} ^{2} }{n_{1}} + \frac{s_{2}^{2} }{n_{2}} } }[/tex]
[tex]Z = \frac{0.486 - 0.359 }{\sqrt{\frac{0.03496 }{42} + \frac{0.02496 }{42} } }[/tex]
[tex]Z = \frac{0.127 }{\sqrt{0.001468}}[/tex]
[tex]Z = \frac{0.127 }{0.0377}[/tex]
⇒Z(cal) = 3.3687
Z(tab) = 1.96
As Z (cal) > Z(tab)
So, we reject H0 at 5% Level of significance
p-value = 0.99962
Hence
There is significant difference in mean conductivity at the two materials.
Which is a better deal on a $345 item: 40% off original price or 30% off and additional 15% at the register?
Answer:
345 - 40% = 207$
Step-by-step explanation:
(345 - 30%) - 15% = 205.3 (Better deal)
Answer:
30% off and additional 15% at the register
Step-by-step explanation:
Deal 1
$345 × 40% = $138
$345 - $138 = $207
Deal 2
$205.30
Please help me.
how many observations are in this data set?
Answer:
16
Step-by-step explanation:
count the dots. each is one observation
Give Brainliest for the correct Answer 50 points
Answer:
x-30
Step-by-step explanation:
Answer: 5(x-2)=40 5x-10 = 40 5x=50 x=10
Step-by-step explanation:
^
Factor the expression
10x + 25
A. 2(5x + 10)
B. 5(2x + 5)
C. 10(x + 5)
D. 5(2x + 25)
Answer:
B. 5(2x+5)
Step-by-step explanation:
Factor 5 out of 10x+25. and you get 5(2x+5)
Answer:
B. 5(2x + 5
Step-by-step explanation:
If you have any questions feel free to ask in the comments
The manager of a restaurant recorded how many people were in different groups of
customers and how much those groups spent on food and beverages. The scatterplot below
shows the data she recorded.
Answer:
$135
Step-by-step explanation:
Answer:
D
Step-by-step explanation:
hows it goin my boi
A new car is purchased for 22300 dollars. The value of the car depreciates at 7.5% per
year. To the nearest year, how long will it be until the value of the car is 7700 dollars?
Answer:I think 3 years
Step-by-step explanation:
sorry if im wrong
Which graphs of ordered pairs represent functions?
Answer:
I thin its b.
Step-by-step explanation:
Zane is putting the strings on 5 harps. Each harp has 48 strings.
How many strings does Zane need for all 5 harps?
Answer:
Zane needs 240 strings for 5 harps.
Step-by-step explanation:
All you have to do is multiply
48 * 5 = 240
So, the answer is 240
Hope this helps! :)
What is the equation of the circle shown in the graph?
6 9 12 36
At the pet fair, Darlene’s dog
weighed 5 times as many pounds
as Leah’s dog. Together, the dogs
weighed 60 pounds.
How many pounds does Leah’s
dog weigh?
Answer:
Darlene's dog weighs 10 pounds.
Step-by-step explanation: 5 x 10 = 50 and 50 + 10 = 60 pounds.
Hope this helps.
What is the slope of the line that passes through the points (3, 2) and (−1,2)? Write your answer in the simplest form
Answer:
slope = 0
Step-by-step explanation:
To find the slope of a line that passes between a pair of points, use the slope formula, [tex]m = \frac{y_2-y_1}{x_2-x_1}[/tex]. Substitute the x and y values of the points (3,2) and (-1,2) into the formula and simplify:
[tex]m = \frac{(2)-(2)}{(-1)-(3)} \\m = \frac{2-2}{1-3} \\m = \frac{0}{-2} \\m=0[/tex]
So, the slope is 0.
o The day before the exam, Rebecca does a practice run. She attempts 20 glass vases and breaks 3 of them. What is her success rate, shown as a decimal?
Answer:
If the goal is to break the vases: 3/20 = 15.0% or 0.15
If the goal is to not break the vases: 17/20 = 85.0% or 0.85
Jaime is employed by Johnson & Johnson making $30 an hour. She had $400 in sales, which
she receives an 8% commission. If she worked 20 hours last week, what was her weekly
pay?
Answer:
$632
Step-by-step explanation:
Set up an equation:
$30(20 hours) + ($400 × 0.08)
$600 + $32
$632
the answer to 2x+56=
Answer:
It can't be simplified or added together because one is multiplied by x and the other is not
Step-by-step explanation:
Complete the sentence: An unbiased estimator is _____. a. any sample statistic used to approximate a population parameter b. a sample statistic, which has an expected value equal to the value of the population parameter c. a sample statistic whose value is usually less than the value of the population parameter d. any estimator whose standard error is relatively small
Answer:
a) Any sample statistic used to approximate a population parameter.
Step-by-step explanation:
An unbiased estimator is any sample statistic used to approximate a population parameter.
In mathematics, the bias of an estimator refers to the difference between the true value of the parameter being estimated and the estimator’s expected value.
If a statistic is not an underestimate or overestimate of the population parameter, then it is unbiased.
That is why an unbiased estimator is an accurate sample statistic used to approximate a population parameter.
What is the answer please I need help if you send a link I will report because your just trying to scam someone
Answer:
The median is 6.
Step-by-step explanation:
which angles are vertical to each other
Answer:
You need to attach the picture of the angles
Answer:
right
Step-by-step explanation: because ones left and 1 right
What is the area of the parallelogram
shown above?
[?] square feet
Answer:
299 square feet
Step-by-step explanation:
Area of a parallelogram = base × height
Base = 23 ft
Height = 13 ft
Note: the other length, 15 ft is not needed in calculating area of the parallelogram. All we need is just the length of the base and the height.
Area of the parallelogram shown = 23 × 13
Area = 299 ft²
solve the equation f/3+22=17
Answer:
f = -15
Step-by-step explanation:
f/3 + 22 - 22 = 17 - 22
f/3 + 0 = -5
f/3 = -5
f = 3 × (-5)
f = -15
Thus, The answer is -15
-TheUnknownScientist
HAHA. YOU GOT IT WRONG ONYEBUCHINNAJI
WHY DID YOU EVEN PUT THIS NAME??
Answer:
free points ty
what is the value of x in the equation -6 + x = -5
In August an online store sold 213 graphing calculators during their back to school sale. Since then, sales have increased at a rate of 5% each month. Which function can be used to determine the monthly calculator sales sine August?
Answer:
[tex]y = 213 + 0.05x[/tex]
Step-by-step explanation:
Given
[tex]Initial = 213[/tex]
[tex]Rate = 5\%[/tex]
The equation to o this is:
[tex]y = intial +rate * weeks[/tex]
[tex]y = 213 + 0.05x[/tex]
VERY EASY, WILL GIVE 50 POINTS FOR CORRECT ANSWER ASAP AND WILL GIVE BRAINLIEST.
Answer: (4,-11)
Step-by-step explanation: To perform a 180 degree rotation we switch the signs of the coordinates
Answer:
4,-11
Step-by-step explanation:
The answer is 4,-11 because if you think that you go over -4 and go up 11. Now switch the negative sign to the y coordinate because it is a 180 degree turn then you have your answer. 4,-11
pls mark as brainliest!!
A company that manufactures tires produces a tire that has average life span of 65,000 kilometers with a standard deviation of 5,200 kilometers. The distribution of the life spans of the tire is normal. What percent of the tires last at least 60,000 kilometers ?
Answer:
=> P(X <= 62500) = P((X-mean)/sd < (62500-65000)/3000)
= P(Z < -0.8333)
= 1 - P(Z < 0.8333)
= 1 - 0.7967
= 0.2033
=> P(X > 68500) = P(Z > (68500-65000)/3000)
= P(Z > 1.1667)
= 0.1210
=> P(60500 < X < 69500) = P((60500-65000)/3000 < Z < (69500-65000)/3000 )
= P(-1.5 < Z < 1.5)
= 0.8664
=> for P(X < x) = 0.03, for Z = -1.88
X = mean + Z*Sd = 65000 - (1.88*3000) = 59360
Step-by-step explanation:
I'm not sure if that correct , I really try my best to help
The required percent of tires last at least 60,000 kilometers is about 91%.
What is the standard deviation?The standard deviation mathematical and statistical analysis tool used to explain the diversity of treatments or values around the Mean is the standard deviation,
To solve this problem, we need to use the standard normal distribution. This is a special type of normal distribution where the mean is 0 and the standard deviation is 1. We can use this to standardize the tire life spans by subtracting the mean (65,000 km) and dividing by the standard deviation (5,200 km).
This gives us a standard normal distribution with a mean of 0 and a standard deviation of 1, and we can use a table or calculator to find the probability of a tire lasting at least 60,000 kilometers.
To do this, we need to find the probability that a tire lasts less than 60,000 kilometers and subtract this from 1. This probability is:
P(tire life < 60,000 km) = P(z < (60,000 - 65,000) / 5,200)
Where z is the standardized tire life span, and the probability is calculated using the standard normal distribution.
Calculating this, we find that P(tire life < 60,000 km) = P(z < -1.346) = 0.0913
Therefore, the probability that a tire lasts at least 60,000 kilometers is 1 - 0.0913 = 0.9087 or about 91%.
Learn more about the standard deviation here:
brainly.com/question/14747159
#SPJ2
The average daily maximum temperature for Shane’s hometown can be modeled by the function f(x)=12.2cos(πx6)+54.9, where f(x) is the temperature in °F and x is the month.
x = 0 corresponds to January.
What is the average daily maximum temperature in March?
Round to the nearest tenth of a degree if needed.
Answer:
The average daily maximum temperature in March is of 61 degrees.
Step-by-step explanation:
The average daily maximum temperature in his hometown in x months after January is given by:
[tex]f(x) = 12.2\cos{(\frac{\pi x}{6})} + 54.9[/tex]
What is the average daily maximum temperature in March?
March is 3 - 1 = 2 months after January, so this is f(2).
[tex]f(2) = 12.2\cos{(\frac{\pi*2}{6})} + 54.9 = 61[/tex]
The average daily maximum temperature in March is of 61 degrees.
answer of the question
Answer:
The number of milk chocolate pieces is between 115 and 120 pieces.
Step-by-step explanation:
PLEASE HELP ME I WILL HIVE BRAINLIST TO THE CORRECT ANSWER !!!!!!!!!!!
Answer:
I'm not 100 percent sure but I think it's the first answer choice because at 40000 3 years have passed. Hope this helps :)
Answer:
The machinery ages three years for every $10,000 loss in value.
Step-by-step explanation:
We can see from the graph that each year, the machinery loses a value of $5,000 (Goes from $50,000 to $45,000 after year one, from $45,000 to $40,000 after year two etc). So we can discount the last two answers.
If it loses $5,000 each year, it loses $15,00 after ageing three years, and $25,00 after five years. Though neither of the first two answers correspond to this, the first answer is closest.
