Suppose that the function g is defined, for all real numbers, as follows.
When (81x^2/7) (2/9x^3/7) is simplified, it can be written in the form ax^b where a and b are real numbers. Find ab.
Answer:
In improper form your solution will be [tex]\frac{90}{7}[/tex]. As a mixed fraction it will be [tex]12\frac{6}{7}[/tex].
Step-by-step explanation:
The first thing we want to do here is to simplify this expression. After doing so, " a " and " b " should be multiplied to result in a possible improper fraction,
[tex]\left(81x^{\frac{2}{7}}\right)\:\left(2/9x^{\frac{3}{7}}\right)\:[/tex] - Apply exponential rule " [tex]\:a^b\cdot \:a^c=a^{b+c}[/tex] "
= [tex]81\cdot \frac{2}{9}x^{\frac{2}{7}+\frac{3}{7}}[/tex] - Combine fractions [tex]\frac{2}{7}[/tex] and [tex]\frac{3}{7}[/tex]
= [tex]81\cdot \frac{2}{9}x^{\frac{5}{7}}[/tex] - Multiply the fractions, and simplify further
= [tex]\frac{162x^{\frac{5}{7}}}{9}[/tex] = [tex]18x^{\frac{5}{7}}[/tex] - This is out simplified expression
Now that we have this simplified expression, we can see that a = [tex]18[/tex], and b = [tex]\frac{5}{7}[/tex]. Therefore, multiplying the two we should receive the improper fraction as follows,
[tex]18 * \frac{5}{7}[/tex] = [tex]\frac{90}{7}[/tex] - Note that this is in improper form. If you want your solution in a mixed fraction, it will be [tex]12\frac{6}{7}[/tex].
A survey of 128 DeVry statistics students found that 83% read the announcements each week. What is the population and what is the sample
Answer:
-Population is DeVry statistics students - Sample is 128 DeVry statistics students.
Step-by-step explanation:
First of all, population is defined as a set of all elements while sample includes some or all those of elements, whereas, sample never includes more elements when compared to population.
Hence, we select sample from the population.
Now, in this question, the survey include 128 DeVry statistics students. Thus, these 128 statistics students would be a sample while total number of Devry statistics students will be the population.
83% is the sample statistic because it gives us numerical information about the sample.
Thus, we can conclude that;
-Population is DeVry statistics students - Sample is 128 DeVry statistics students.
Find a formula for the general term an of the sequence, assuming that the pattern of the first few terms continues. (Assume that n begins with 1.) −3, 2, − 4 3 , 8 9 , − 16 27 , ...
Answer:
The general term is
Sn = -(-2)ⁿ.3¹⁻ⁿ
step by step Explanation:
we were told to find a general term of the above sequence, what should come to mind is that the terms will follow an order....
CHECK THE ATTACHMENT FOR DETAILED EXPLANATION
Type the correct answer in the box. Use numerals instead of words. If necessary, use / for the fraction bar.
The table gives the boiling point of water at different altitudes.
Altitude (1,000 feet) Boiling Point of Water (°F)
0 212.0
0.5 211.1
1.0 210.2
2.0 208.4
2.5 207.5
3.0 206.6
4.0 204.8
4.5 203.9
Based on the table, the linear equation that represents the change in water’s boiling point for every 1,000-foot change in altitude has a slope of
units.
Answer:
[tex]\large \boxed{\text{-1.8$^{\circ}$F/1000 ft}}[/tex]
Step-by-step explanation:
Identify the changes (Δ) in each consecutive pair of x-values and y-values, then calculate the corresponding values of Δy/Δx
Your working table should look like the one below.
[tex]\begin{array}{cccc}\textbf{Alt/1000 ft} & \textbf{B.p.$/^{\circ}$F} & \Delta\textbf{B. p}& \Delta\textbf{B.p/1000 ft}\\0 & 212.0 & & \\& &-0.9 & -1.8\\0.5 & 211.1 & & \\& &-0.9 & -1.8\\1.0 & 210.2 & & \\& &-1.8 & -1.8\\2.0 & 208.4 & & \\& &-1.8 & -1.8\\3.0 & 206.6 & & \\& &-1.8 & -1.8\\4.0 & 204.8 & & \\& &-0.9 & -1.8\\4.5 & 203.9 & & \\\end{array}[/tex]
[tex]\text{ The change in boiling point per thousand feet of altitude is $\large \boxed{\textbf{-1.8$^{\circ}$F/1000 ft}}$}[/tex]
Answer:
Answer:
Step-by-step explanation:
Identify the changes (Δ) in each consecutive pair of x-values and y-values, then calculate the corresponding values of Δy/Δx
Your working table should look like the one below.
Step-by-step explanation:
The houses on a city block were valued at $172,000, $164,000, $142,000,
$159,000, $191,000, $124,000, and $146,000, respectively. But a public
assessor has determined that the value of each house is actually $13,000
higher than previously thought. According to the public assessor, what is the
median value of the houses?
A. $159,000
B. $165,000
C. $172,000
D. $177,000
Answer:
C. $172,000
Step-by-step explanation:
Calculation for the median value of the houses
The following data was given in the question:$172,000, $164,000, $142,000,
$159,000, $191,000, $124,000, and $146,000
The first step is to Arrange the above data in ascending order
$124,000,$142,000,$146,000,$159,000,
$164,000,$172,000,$191,000
Second step is to find the Median
The Median will be the mid value, which means that $159,000 is the mid value
Based on the information given in the question we were given that a public
assessor has determined that the value of each house is actually $13,000 higher than previously thought
Hence, the Median will be = $159,000+$13,000=$172,000
Therefore the median value of the houses will be $172,000
PLEASE HELP!! Find the missing side and round answer to the nearest tenth.
Answer:
Step-by-step explanation:
opp=x,hyp=16
sin 51°=[tex]\frac{x}{16}[/tex]
cross multiply
sin 51° x 16 =x
0.7771 x 16=x
12.4=x
What is the equation of the line in slope-intercept form that is perpendicular to the line y=3/4x-2 and passes
through the point (-12, 10)?
Oy=-4/3-6
O y=-4/3x + 6
O y = 4/3x + 26
O y = 4/3x +10
Answer: y=-(4/3)*x-6
Step-by-step explanation:
The equation of any straight line is y=a*x+b (1).
So we have to find the coefficients a and b and substitute them to the equation (1).
If the required line is perpendicular to y= (3/4)*x-2 it means that
a= -(4/3) (we have to inverse the fraction 3/4 and put the opposite sign after that. 3/4 has the sign + in front of it so we have to put sign -)
So the equation of required line is y= -(4/3) *x+b .
Now we have to find b. To do that pls remember that the point (-12;10) belongs to the required line y= -(4/3) *x+b . That means:
10=-(4/3)*(-12)+b => 10=16+b => b=-6
So substitute b in equation (1) and get:
y=-(4/3)*x-6
Applying the Segment Addition Postulate
Point B lies between points A and C on AC. Let x
represent the length of segment AB in inches.
A
B
3x
Use the segment to complete the statements.
The value of x is v.
The length of AR in inches is
✓x
C
The length of BC in inches is
20 inches
Intro
Answer:
x = 5, AB=5, BC = 15
Step-by-step explanation:
AC = AB + BC (Segment Addition)
AC= 20, AB =x Bc = 3x,
20= x+3x 20=4x
x=5
AB=x, AB =5
BC=3x BC= 15
The segment addition postulate states gives the value of x as 5, given
that the sum of x and 3·x is 20.
Responses:
The value of x is 5The length of [tex]\overline{AB}[/tex] is 5 inchesThe length of [tex]\overline{BC}[/tex] is 15 inchesHow does segment addition postulate give the value of x?From the given diagram, we have;
[tex]\overline{AB}[/tex] = x
[tex]\overline{BC}[/tex] = 3·x
According to segment addition postulate we have;
[tex]\overline{AB}[/tex] + [tex]\overline{BC}[/tex] = [tex]\overline{AC}[/tex] = 20 inches
Which gives;
x + 3·x = 20
Therefore;
4·x = 20
[tex]x = \dfrac{20}{4} = 5[/tex]
The value of x is 5The length of [tex]\overline{AB}[/tex] is 5 inches[tex]\mathbf{\overline{BC}}[/tex] = 3·x
[tex]\mathbf{\overline{BC}}[/tex] = 3 × 5 = 15
The length of [tex]\overline{BC}[/tex] is 15 inchesLearn more about segment addition postulate here:
https://brainly.com/question/1397818
find the sum (12p +9) +(4p-3)
Hey there! :)
Answer:
16p + 6.
Step-by-step explanation:
Add the two binomials together by combining like terms:
12p + 9 + 4p - 3
12p + 4p + 9 - 3
16p + 6.
Answer:
16p+6
Step-by-step explanation:
You combine like terms you do not multiply.
What are the solutions to the system of equations graphed below?
Answer:
Hey there!
The solutions to a system are where the lines, or graphs intersect each other.
We see that the graphs intersect at (0, -4) and (2, 0).
Thus, the solutions are (0, -4) and (2, 0).
Hope this helps :)
Assume that a sample is used to estimate a population proportion p. Find the 99% confidence interval for a sample of size 315 with 37% successes. Enter your answer as an open-interval (i.e., parentheses) using decimals (not percents) accurate to three decimal places.
Answer:
The 99% confidence interval is = 0.37 +/- 0.070
= (0.300, 0.440)
Step-by-step explanation:
Confidence interval can be defined as a range of values so defined that there is a specified probability that the value of a parameter lies within it.
The confidence interval of a statistical data can be written as.
p+/-z√(p(1-p)/n)
Given that;
Proportion p = 37% = 0.37
Number of samples n = 315
Confidence interval = 99%
z value(at 99% confidence) = 2.58
Substituting the values we have;
0.37 +/- 2.58√(0.37(1-0.37)/315)
0.37 +/- 2.58√(0.00074)
0.37 +/- 2.58(0.027202941017)
0.37 +/- 0.070183587825
0.37 +/- 0.070
= (0.300, 0.440)
The 99% confidence interval is = 0.37 +/- 0.070
= (0.300, 0.440)
The net price equivalent rate of 9 / 15 / 18 is
Answer:
f so final percentage
= .91(.85)(.82) = .63427
or 63.427% of the original price
Step-by-step explanation:
An earthquake was felt throughout a circular area of 1,808.64 square miles. What was the radius of the circular area?
Answer:
24 miles
Step-by-step explanation:
The area of a circle is given by: A = (pi)(r^2)
The problem gives the area as: 1,808.64 sq. mi.
So, (pi)(r^2) = 1,808.64 Solve for r. Divide both sides by pi (3.14)
r^2 = 1.808.64/3.14
r^2 = 576 Take the square root of both sides.
r = 24 Miles.
Answer:
23.99 miles
Step-by-step explanation:
The area of a circle is denoted by A = πr², where r is the radius.
Here, we know the circular area is A = 1808.64 square miles, so plug this into the formula to find r:
A = πr²
1808.64 = πr²
r² = 1808.64 / π ≈ 575.71
r = √575.71 ≈ 23.99 miles
The answer is thus 23.99 miles.
~ an aesthetics lover
Shaun's tent (shown below) is a triangular prism. Find the surface area, including the floor, of his tent.
Answer: 52.8
Step-by-step explanation: it’s on khan ,
The accompanying data represent the total travel tax (in dollars) for a 3-day business trip in 8 randomly selected cities. A normal probability plot suggests the data could come from a population that is normally distributed. A boxplot indicates there are no outliers.
67.85 78.62 70.28 84.03 79.28 87.72 101.54 97.28
1. Determine a point estimate for the population mean travel tax.
2. Construct and interpret a 95% confidence interval for the mean tax paid for a three-day business trip.
Filling the missing boxes.
The lower bound is $_______and the upper bound is $_______. One can be______% confident that all cities have a travel tax between these values.
The lower bound is $______and the upper bound is $______. The travel tax is between these values for______% of all cities.
The lower bound is $_____and the upper bound is $______. There is a_______% probability that the mean travel tax for all cities is between these values.
The lower bound is $_______and the upper bound is______. One can be______% confident that the mean travel tax for all cities is between these values.
3. What would you recommend to a researcher who wants to increase the precision of the interval, but does not have access to additional data?
A. The researcher could decrease the level of confidence.
B. The researcher could decrease the sample standard deviation.
C. The researcher could increase the level of confidence.
D. The researcher could increase the sample mean.
Answer:
1. Point estimate M (sample mean): 83.33
2. The lower bound is $73.36 and the upper bound is $93.30. One can be______% confident that the mean travel tax for all cities is between these values.
3. A. The researcher could decrease the level of confidence.
Step-by-step explanation:
A point esimate for the population mean travel tax can be done with the sample mean.
We can calculate the sample mean as:
[tex]M=\dfrac{1}{n}\sum_{i=1}^n\,x_i\\\\\\M=\dfrac{1}{8}(67.85+78.62+70.28+84.03+79.28+87.72+101.54+97.28)\\\\\\M=\dfrac{666.6}{8}\\\\\\M=83.33\\\\\\[/tex]
2. We have to calculate a 95% confidence interval for the mean.
The sample mean is M=83.33.
The sample size is N=8.
The population standard deviation is not known, so we have to estimate it from the sample standard deviation and use a t-students distribution to calculate the critical value.
We calculate the sample standard deviation as:
[tex]s=\sqrt{\dfrac{1}{n-1}\sum_{i=1}^n\,(x_i-M)^2}\\\\\\s=\sqrt{\dfrac{1}{7}((67.85-83.33)^2+(78.62-83.33)^2+(70.28-83.33)^2+. . . +(97.28-83.33)^2)}\\\\\\s=\sqrt{\dfrac{994.49}{7}}\\\\\\s=\sqrt{142.07}=11.92\\\\\\[/tex]
The standard error is:
[tex]s_M=\dfrac{s}{\sqrt{N}}=\dfrac{11.92}{\sqrt{8}}=\dfrac{11.92}{2.828}=4.214[/tex]
The degrees of freedom for this sample size are:
[tex]df=n-1=8-1=7[/tex]
The t-value for a 95% confidence interval and 7 degrees of freedom is t=2.36.
The margin of error (MOE) can be calculated as:
[tex]MOE=t\cdot s_M=2.36 \cdot 4.214=9.97[/tex]
Then, the lower and upper bounds of the confidence interval are:
[tex]LL=M-t \cdot s_M = 83.33-9.97=73.36\\\\UL=M+t \cdot s_M = 83.33+9.97=93.30[/tex]
The 95% confidence interval for the mean travel tax is (73.36, 93.30).
We can be 95% confident that the true mean travel tax is within this interval.
3.. If we have no access to additional data, we can not decrease the standard deviation or increase the sample size.
The only way to have a narrower confidence interval is decreasing its level of confidence. With the same sample information, the lower the confidence, the narrower is the interval.
Ok, so. I know It’s -27 + 23x and X = 7 right?? Or am I doing something wrong.
Answer:
134 degrees
Step-by-step explanation:
Right so far. To find the numerical measure of the angle, you need to use x=7 in your expression for the angle measure:
m∠STU = -27 +23(7) = 134 . . . degrees
What is the value of x?
45
m
(2x-5)
Answer:
if m is supposed to be the equals (=) sign then x = 25
Step-by-step explanation:
45 = (2x-5)
+5 +5
50 = (2x)
÷2 ÷2
25 = x
Answer: 70
Step-by-step explanation:
Click on the graphic below until RA TU at point Q is displayed. Plzzzzz help
Answer:
I think its
T
R--------Q----------A
U
Step-by-step explanation:
Because RA as a line bisects TU
Please help me the venn diagram is wrong too im confused on how to do this :(((
Answer:
probability of chosing a student that has a cat and a dog is 9/25
Step-by-step explanation:
And yes the Venn diagram is wrong because you forgot to subtract 9 from 15 and 16
This makes it
[ 3 ( 6 ( 9 ) 7 ) ]
3 + 6 + 9 + 7 = 25
Solve the system of equations: [tex]3x-4y=-23\\2y-x=-19[/tex]
Answer:
Step-by-step explanation:
3x - 4y = -23
-x + 2y = -19
3x - 4y = -23
-3x - 6y = -57
-10y = -80
y = 8
-x + 2(8) = -19
-x + 16 = -19
-x = -35
x = 35
(35, 8)
━━━━━━━☆☆━━━━━━━
▹ Answer
(-61, -40)
▹ Step-by-Step Explanation
3x - 4y = -23
2y - x = -19
3x - 4y = -23
x = 19 + 2y
3(19 + 2y) - 4y = -23
y = -40
x = 19 + 2 * (-40)
x = -61
(x, y) = (-61, -40)
Hope this helps!
- CloutAnswers ❁
Brainliest is greatly appreciated!
━━━━━━━☆☆━━━━━━━
John didnt have money for a game system, so he bought it with his credit card. he paid for it monthly over the course of a year. The $350.00 game system ended up costing $429, What percentage of the game system price did he pay in interest?
Answer:
percentage of interest = 22.6% (to one decimal place)
Step-by-step explanation:
actual price paid (including interest) = 429, out of which
interest = 429-350 = 79
Percentage of interest out of actual price paid
= 79/429* 100%
= 22.6%
Kimberly is a program director for the channel KID. She tracked the cartoons shown on the channel for a week. The probability that the show had animals in it was 0.7. The probability that the show aired more than 10 times was 0.4. The probability that the show had animals in it and aired more than 10 times was 0.2. Which equation shows the correct use of the addition rule to determine the probability that a randomly selected show had animals in it or aired more than 10 times?
Options
0.7+0.2−0.4=0.5 0.7+0.2=0.9 0.7+0.4=1.1 0.4+0.2=0.6 0.7+0.4−0.2=0.9Answer:
[tex](E)0.7+0.4-0.2=0.9[/tex]
Step-by-step explanation:
In probability theory
[tex]P$(A or B)=P(A)+P(B)$-$P(A and B)[/tex]
Let the event that the show had animals in it = A
P(A)=0.7
Let the event that the show aired more than 10 times =B
P(B)=0.4
P(A and B)= 0.2
[tex]P$(A or B)$=0.7+0.4-0.2=0.9[/tex]
Therefore, the equation which shows the correct use of the addition rule to determine the probability that a randomly selected show had animals in it or aired more than 10 times is:
[tex]0.7+0.4-0.2=0.9[/tex]
The correct option is E.
A clinical trial tests a method designed to increase the probability of conceiving a girl. In the study 290 babies were born, and 261 of them were girls. Use the sample data to construct a 99% confidence interval estimate of the percentage of girls born. Based on the result, does the method appear to be effective?
Answer:
The 99% confidence interval estimate of the percentage of girls born is between 85.46% and 94.54%.
Usually, babies are equally as likely to be boys or girls. Here, it is desired to increase the probability of conceiving a girl, which is achieved, considering the lower bound of the confidence interval is considerably above 50%.
Step-by-step explanation:
Confidence interval for the proportion:
In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.
[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
In which
z is the zscore that has a pvalue of [tex]1 - \frac{\alpha}{2}[/tex].
For this problem, we have that:
[tex]n = 290, \pi = \frac{261}{290} = 0.9[/tex]
99% confidence level
So [tex]\alpha = 0.01[/tex], z is the value of Z that has a pvalue of [tex]1 - \frac{0.01}{2} = 0.995[/tex], so [tex]Z = 2.575[/tex].
The lower limit of this interval is:
[tex]\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.9 - 2.575\sqrt{\frac{0.9*0.1}{290}} = 0.8546[/tex]
The upper limit of this interval is:
[tex]\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.9 + 2.575\sqrt{\frac{0.9*0.1}{290}} = 0.9454[/tex]
Percentage:
Proportion multplied by 100.
0.8546*100 = 85.46%
0.9454*100 = 94.54%
The 99% confidence interval estimate of the percentage of girls born is between 85.46% and 94.54%.
Based on the result, does the method appear to be effective?
Usually, babies are equally as likely to be boys or girls. Here, it is desired to increase the probability of conceiving a girl, which is achieved, considering the lower bound of the confidence interval is considerably above 50%.
Rewrite 100⋅(200⋅300) using the Associative Law of Multiplication.
Answer:
6 x 10⁶ or 6,000,000
Step-by-step explanation:
100 × (200 × 300)
100 x 60,000 → 6,000,000
6,000,000 → 6 x 10⁶
Hope this helps! :)
I NEED HELP PLEASE, THANKS! :)
Write 18(cos169° + isin169°) in rectangular form. Round numerical entries in the answer to two decimal places. (Show work)
Answer:
z = -17.67 + i3.43
Step-by-step explanation:
Let us apply the formula z = r(cos Ф + i sin Ф), given 18(cos169° + isin169°) -
z = 18( cos169 + isin169 ),
z = r(cos Ф + i sin Ф)
Now we can solve this question in the form z = a + bi, in this case where a = 18 cos169, and b = 18 sin169. This is as a = r cos Ф and b = r sin Ф -
sin169 is positive, while cos169 is negative, thus -
a = -17.6692893021...,
b = 3.43456191678...
Rectangular Form, z = -17.67 + i3.43
Hope that helps!
Given the domain {-4, 0, 5}, what is the range for the relation 12x + 6y = 24?
Hey there! I'm happy to help!
The domain is all of the possible x-values and the range is all of the possible y-values.
Let's quickly rearrange our equation so we can plug in x to see what y is.
12x+6y=24
We subtract 12x from both sides.
6y=-12x+24
We divide both sides by six.
y= -2x+4
Since there are three domains we can plug into this equation that can give us one output, we will have three numbers in our range! Let's plug in our x-values to get our three y-values.
y=-2(-4)+4
y=12
y=-2(0)+4
y=4
y=-2(5)+4
y= -6
When writing your range, you order the numbers from least to greatest. We can write this range as {-6,4,12}
Have a wonderful day!
solve the eqauation 76a^3+19a^2+16a=-4
Answer:
The solutions are a₁ = -4/19 i, a₂ = 4/19 i and a₃ = -1/4
Step-by-step explanation:
Given the equation 76a³+19a²+16a=-4, for us to solve the equation, we need to find all the factors of the polynomial function. Since the highest degree of the polynomial is 3, the polynomial will have 3 roots.
The equation can also be written as (76a³+19a²)+(16a+4) = 0
On factorizing out the common terms from each parenthesis, we will have;
19a²(4a+1)+4(4a+1) = 0
(19a²+4)(4a+1) = 0
19a²+4 = 0 and 4a+1 = 0
From the first equation;
19a²+4 = 0
19a² = -4
a² = -4/19
a = ±√-4/19
a₁ = -4/19 i, a₂ = 4/19 i (√-1 = i)
From the second equation 4a+1 = 0
4a = -1
a₃ = -1/4
Tensile strength tests were carried out on two different grades of wire rod, resulting in the accompanying data.
Grade Sample Size sample mean(kg/mm^2) Sample S
AISI 1064 m = 126 x = 102.8 s1 = 1.2
AISI 1078 n = 126 y = 121.3 s2 = 2.0
a. Does the data provide compelling evidence for concluding that true average strength for the 1078 grade exceeds that for the 1064 grade by more than 10 kg/mm^2.
b. Test the appropriate hypotheses using the P-value approach.
c. Calculate the test statistic and p-value.
d. State the conclusion in the problem context.
Answer:
The null hypothesis is rejected.
There is enough evidence to support the claim that the true average strength for the 1078 grade exceeds that for the 1064 grade by more than 10 kg/mm^2.
Test statistic t=-40.91
P-value = 0
Step-by-step explanation:
This is a hypothesis test for the difference between populations means.
The claim is that the true average strength for the 1078 grade exceeds that for the 1064 grade by more than 10 kg/mm^2.
Then, the null and alternative hypothesis are:
[tex]H_0: \mu_1-\mu_2=-10\\\\H_a:\mu_1-\mu_2< -10[/tex]
The significance level is 0.05.
The sample 1 (AISI 1064), of size n1=126 has a mean of 102.8 and a standard deviation of 1.2.
The sample 2 (AISI 1078), of size n2=126 has a mean of 121.3 and a standard deviation of 2.
The difference between sample means is Md=-18.5.
[tex]M_d=M_1-M_2=102.8-121.3=-18.5[/tex]
The estimated standard error of the difference between means is computed using the formula:
[tex]s_{M_d}=\sqrt{\dfrac{\sigma_1^2}{n_1}+\dfrac{\sigma_2^2}{n_2}}=\sqrt{\dfrac{1.2^2}{126}+\dfrac{2^2}{126}}\\\\\\s_{M_d}=\sqrt{0.011+0.032}=\sqrt{0.043}=0.2078[/tex]
Then, we can calculate the t-statistic as:
[tex]t=\dfrac{M_d-(\mu_1-\mu_2)}{s_{M_d}}=\dfrac{-18.5-(-10)}{0.2078}=\dfrac{-8.5}{0.2078}=-40.91[/tex]
The degrees of freedom for this test are:
[tex]df=n_1+n_2-2=126+126-2=250[/tex]
This test is a left-tailed test, with 250 degrees of freedom and t=-40.91, so the P-value for this test is calculated as (using a t-table):
[tex]\text{P-value}=P(t<-40.91)=0[/tex]
As the P-value (0) is smaller than the significance level (0.05), the effect is significant.
The null hypothesis is rejected.
There is enough evidence to support the claim that the true average strength for the 1078 grade exceeds that for the 1064 grade by more than 10 kg/mm^2.
Please help ?!!! Solve the three equations in the table using any method of your choice. List the method you used.
Equation
x^2-4=-12
-9x^2+4x-10=0
x^2+8x=-17
With solutions and method
Step-by-step explanation:
[tex]x = \frac{ - b \frac{ + }{ - } \sqrt{ {b}^{2} - 4ac } }{2a} [/tex]
The quadratic formula is honestly the most straightforward way of solving here.
Your other options are completing the square (which is the same thing as the quadratic formula but it's good to know that method if you have to take Integral Calculus at some point) or maybe factoring by grouping if it's appropriate. But the quadratic formula will work for you in all three equations:
1) a=1, b=0, c=8
This reduces pretty quickly into x=8i,-8i due to the negative under the radical. (Actually we didn't even really need the formula here.)
2) a=-9, b=4, c=-10
This reduces into x=(-4+i√(344))/-18, (-4-i√(344))/-18 and doesn't go any further because 344 isn't a perfect square.
3) a=1, b=8, c=17
This reduces to x=(-4+i), (-4-i)
So those are the answers for each.
Please Refer to the screenshot. Hope this helps!