Answer:
7x-5
Step-by-step explanation:
A tire manufacturer is interested in testing the fuel economy for two different tread patterns. Tires of each tread type are driven for 1000 miles on each of 18 different cars. In a separate experiment, 18 cars were outfitted with tires with tread type A, and another 18 were outfitted with tires with tread type B. Each car was driven 1000 miles. The cars with tread type A averaged 23.95 mpg, with a standard deviation of 1.79 mpg. The cars with tread type B averaged 22.19 mpg, with a standard deviation of 1.95 mpg. Let μX represent the population mean mileage for tread type A and let μY represent the population mean mileage for tread type B.
Required:
Find a 99% confidence interval for the difference μXâμY. Round the answers to three decimal places.
Using the t-distribution, it is found that the 99% confidence interval for the difference is (0.058, 3.462).
We are given the standard deviation for the samples, hence, the t-distribution is used to solve this question.
The standard errors are given by:
[tex]s_A = \frac{1.79}{\sqrt{18}} = 0.4219[/tex]
[tex]s_B = \frac{1.95}{\sqrt{18}} = 0.4596[/tex]
For the distribution of differences, the mean and the standard error are given by:
[tex]\overline{x} = \mu_A - \mu_B = 23.95 - 22.19 = 1.76[/tex]
[tex]s = \sqrt{0.4219^2 + 0.4596^2} = 0.6239[/tex]
The interval is given by:
[tex]\overline{x} \pm ts[/tex]
The critical value for a two-tailed 99% confidence interval with 18 + 18 - 2 = 34 df is t = 2.7284.
Then:
[tex]\overline{x} - ts = 1.76 - 2.7284(0.6239) = 0.058[/tex]
[tex]\overline{x} + ts = 1.76 + 2.7284(0.6239) = 3.462[/tex]
The 99% confidence interval for the difference is (0.058, 3.462).
For more on the t-distribution, you can check https://brainly.com/question/16162795
If Y has exactly 2 positive integer factors then Y is a prime number. if so how?
Step-by-step explanation:
yes, if your teacher meant to include the default factors of every positive integer number : 1 and the number itself.
these are the 2 positive integer factors.
if a positive number can only be divided without remainder by 1 or by itself (with result 1), then it is per definition a prime number.
if the number can be divided without remainder by another number, then we are not dealing with a prime number.
but if your teacher did not have these default factors in mind, then no :
example : 15
15 has only 2 factors : 3 and 5.
both are positive integer numbers.
and yet 15 is not a prime number.
but back to my first point, 15 also has formally the factors 1 and 15. so, if we count them too, then we have suddenly 4 factors. and the original statement fits again.
Snow fell from 6:30 am to 11:00 am, accumulating at a constant rate. At 8:00 am, the snow was 8 inches deep. By 11:00 am, it was 20 inches deep. How much snow fell each hour? (Part one)
The answer to the first box would be 4
Answer:
4 for the first box
Step-by-step explanation:
Please take a look at the picture
Answer:
I think it'
is A and B
Step-by-step explanation:
hope hwlps
Multiply or divide. write fractions in simplest form.
-2/7 divided by (-8/21)
please help with this problem i will mark you brainliest :)
Answer:
3/4
Step-by-step explanation:
(-2/7) / (-8/21)
When dividing by a fraction flip it over and multiply
(-2/7) * (-21/8)
Cancel 2 and 8
(-1/7) * (-21/4)
Cancel 7 and 21
(-1/1) * (-3/4)
multiply
3/4
PLEASE HELP PLEASEEE
Answer:
pointts Step-by-step explanation:
u
Answer:
d
Step-by-step explanation:
find the sum or difference of 1/9 - 4 11/12
Answer:
-65/36
Step-by-step explanation:
Find fraction and a decimal between 0.66 and 3/4 .the fraction and decimal should be two different numbers
Answer:
Step-by-step explanation:
0.66=66/100 3/4=75/100
fraction between
67/100 68/100 69/100 70/100 71/100 72/100 73/100 74/100
or or or or
17/25 7/10 18/25 37/50
decimal between
0.67 0.68 0.69 0.70 0.71 0.72 0.73 0.74
the sum of x and 4y is 9
Answer:
y= -1/4x +9/4
Step-by-step explanation:
I don't know which form you wanted, so heres the slope form
Rewrite 5/6 and 6/7 so they have a common denominator
Answer:
a command demonimater of 6 and 7 is 42
35/42 and 36/42
Hope This Helps!!!
select the two values of x that are roots of this equation 3x^2 + 1 = 5x
Answer:
[tex]x = \frac{5 + \sqrt{13} }{6} [/tex]
Step-by-step explanation:
[tex]3x { }^{2} + 1 = 5x[/tex]
[tex]3 {x}^{2} - 5x + 1 = 0[/tex]
Apply the quadratic formula with a=3, b=-5 and c=1The hole for a support needs to be 4 feet deep. It is currently 2 feet 9 inches deep. How much deeper
must the hole be? Use pencil and paper. Show two ways to solve this problem. Use the conversion
12 inches
factor
1 foot
The hole needs to be inches deeper.
Enter your answer in the answer box and then click Check Answer
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T
Answer:
1 ft 3 inches
Step-by-step explanation:
Find the volume of each shape. Round your answer to two decimal places.
Answer:
25
Step-by-step explanation:
25
There are 6 equally sized slices in a pizza. If Ken eats 5 of the slices,
what percent of the pizza has he eaten? Show your work.
Answer:
Step-by-step explanation:
5 / 6 = 0.83333333...
0.833333...•100 = 83.333333...
83.3%
Answer:
You can do this type of questions with inverse proportion.
_
%83,3
Carrie loves carrots so much that she ate 30 of them for lunch. Her sister doesn’t like carrots as much and only ate 5 of them for lunch. The number of carrots Carrie ate is how many times greater than the number that her sister ate?
As the average daily temperature in New York City decreases, the number of persons who are observed wearing sweaters in the workplace increases. This is an example of a __________ correlation. a. causal b. zero c. positive d. negative
When the average daily temperature in New York City decreases, the number of persons who are observed wearing sweaters in the workplace increases, this implies a negative correlation.
Negative correlation simply means the relationship between two variables where as one variable increases, the other variable will reduce.
Therefore, in a situation where the average daily temperature in New York City decreases and the number of persons who are observed wearing sweaters in the workplace increases, this illustrates a negative correlation.
Read related link on:
https://brainly.com/question/25705812
The states that a2 + b2 = c2, when finding the length of a side for a right triangle.
Answer:
Pythagoras Theorem
Step-by-step explanation:
Answer:
so if I do b1+a1=c1 ok me done
Juan has x quarters and y dimes, having a minimum of 16 coins worth at
y
most $3 combined. No less than 4 of the coins are quarters. Solve this system
of inequalities graphically and determine one possible solution.
Is 40 is 50% of 80 true or false
With step by step evidence
Answer:
please mark brainliest
it is true
Step-by-step explanation:
if you multiplie 80 by 0.50 you will get 40,
Which equation represents the statement: Three times the sum of a number and 5 is –30?
3n + 5 = -30
3(n+5) = -30
n + 15 = -30
(n + 5) ÷ 3 = -30
Answer:
3(n+5)=-30
Step-by-step explanation:
Three times the sum of a number and 5 is - 30
Vocabulary:
times = multiplication, represented with *
sum = addition, represented by +
unknown number = n
Three * the sum of a number and 5
The sum of a number and 5 is the same as saying n + 5
So we are multiplying 3 by n + 5
Because n is an unknown variable we have to separate the sum of n and 5 from being multiplied by 3 with parenthesis. We do this because if we want to multiply 3 by the sum of n and 5. If we put 3 * n + 5 we are only multiplying the unknown variable by 3 not including the 5 that is added to it.
So we get 3( n + 5 ) is -30
3(n+5)=-30 is the answer.
Answer:
[tex]3(n+5)=-30[/tex]
Step-by-step explanation:
1. Divide the problem into pieces. The sum of a number and five can be written as [tex]n+5[/tex], where n is any number.
2. Since the question tells us that this sum is multiplied by 3, we expand the expression to [tex]3(n+5)[/tex].
3. Finally, the question tells us that this expression is equal to -30. This means we can express the entire statement as the equation [tex]3(n+5)=-30[/tex].
geomtry plz help 15 points
Answer:
it should be 60°. the single marks on each side means they are all equal
Answer:
m∠L=60º
Step-by-step explanation:
The triangle is an equilateral triangle meaning that all angles and sides are equal.
m∠L=60º
Hope this helps :)
Todd and Tim are exercising. Todd does 20 push-ups at the same time as Tim does 30 push-ups. When Todd does
40 push-ups, how many push-ups does Tim do?
Answer:
50 pushups.
Step-by-step explanation:
simple pattern of adding 10 each time.
increase 400 in the ratio 3:5
decrease 400 in the ratio 3:5
Answer:
Given 3:5 = 3+5=10,
400*3/8=150,
400*5/8=250.
brainy heart rate 190 per minute her heart rate is 70% of her MHR
what is target heart rate
70
120
133
190
217
Answer:
120
Step-by-step explanation:
trough dependent sarcasm
According to the central limit theorem, if a sample of size 100 is drawn from a population with a mean of 80, the mean of all sample means would equal _______. SHOW THE STEPS TO ARRIVE A T THE ANSWER (4 points)
Answer:
μX = the mean of X
σX = the standard deviation of X
If you draw random samples of size n, then as n increases, the random samples
¯¯¯¯¯
X
which consists of sample means, tend to be normally distributed.
¯¯¯¯¯
X
~ N (
μ
x
,
σ
x
√
n
)
The central limit theorem for sample means says that if you keep drawing larger and larger samples (such as rolling one, two, five, and finally, ten dice) and calculating their means, the sample means form their own normal distribution (the sampling distribution). The normal distribution has the same mean as the original distribution and a variance that equals the original variance divided by, the sample size. The variable n is the number of values that are averaged together, not the number of times the experiment is done.
To put it more formally, if you draw random samples of size n, the distribution of the random variable
¯¯¯¯¯
X
, which consists of sample means, is called the sampling distribution of the mean. The sampling distribution of the mean approaches a normal distribution as the sample size n increases.
The random variable
¯¯¯¯¯
X
has a different z-score associated with it from that of the random variable X. The mean
¯¯¯
x
is the value of
¯¯¯¯¯
X
in one sample.
z =
¯¯¯
x
−
μ
x
σ
x
√
n
μ
x
=
μ
¯¯¯
x
(mean of X = mean of
¯¯¯¯¯
X
. )
σ
¯¯¯
x
=
σ
x
√
n
= standard deviation of
¯¯¯¯¯
X
and is called the standard error of the mean.
Step-by-step explanation:
sorry if its hard/ confusing
I need help please please please
Answer:
$28
Step-by-step explanation:
5.5% is $1.54 of what number? (%/100= is/of)
5.5/100 = 1.54/X
X = (1.54 * 100) / 5.5 = $28
Answer:
sus
Step-by-step explanation:
O_O
PLEASE HELP, I'LL GIVE BRAINLIEST!!
Answer:
3
Step-by-step explanation:
I think the answer is 3 because there are 3 spaces between each dot but I am also not the smartest person so if that's right sorry!
1,200 miles; 5% increase
Answer:
5%equals 5 divided by 100 equals 600
George wants to write the number “fifteen thousandths” in standard form. Explain to him how he would do this. Be sure to name the places his digits will go in. What is “fifteen thousandths” in standard form?
Answer:
0.015
Step-by-step explanation:
He would have to take 15 and put the decimal point 4 places to the left of the number.
If a value has thousandths, it goes 4 places to the left, hundredths goes 3 places to the left, tenths goes 2 places to the left and ones goes 1 place to the left.
The standard form is 10,000 + 5000.
What is an expression?An expression contains one or more terms with addition, subtraction, multiplication, and division.
We always combine the like terms in an expression when we simplify.
We also keep all the like terms on one side of the expression if we are dealing with two sides of an expression.
Example:
1 + 3x + 4y = 7 is an expression.
3 + 4 is an expression.
2 x 4 + 6 x 7 – 9 is an expression.
33 + 77 – 88 is an expression.
We have,
Fifteen thousandths
This can be written as,
= 15,000
It can be expanded as,
= 10,000 + 5,000
= 1 ten thousands + 5 thousands
Thus,
The standard form is 10,000 + 5000.
Learn more about expressions here:
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A research question is a declarative statement which can be tested to determine the probability of it being true or false.
Answer:
Step-by-step explanation:
Yes the answer is true.
A declarative statement is one that
makes a statementprovides a factoffers an explanationconveys informationThat being said, it can make a statement that is testable. It is testable, it can be assigned a probability.