Answer:
202
Step-by-step explanation:
First, we can find the conjugate of (-9 -11i)
Given a complex number a + bi, the conjugate would be a - bi.
So, the conjugate of -9 -11i is -9 + 11i.
Now, we multiply!
(-9-11i)(-9+11i)
This resembles the special product (a+b)(a-b) which multiplies out to a^2 - b^2
To apply this we subtract the square of the second number from the first.
(-9)^2 - (11i)^2
81 - 121i^2
i^2 is -1, so we can substitute it in:
81 + 121 = 202
probability of an even number both times
Answer:
1/4
Step-by-step explanation:
The possible outcomes are :
1,2,3,4,5,6
We can see that there is a 3/6 (or 1/2) chance the outcome is even
Let E= odds of getting an even
we're looking for E∩E
Because each roll is independent of the last we can multiply to find their intersection
.5*.5= .25 or 1/4
At which value in the domain does f(x) = 0?
2
2
4
Answer:
4
Step-by-step explanation:
hellpppppppppspspspspspspsp
I'd say 13, hope this helps
Step-by-step explanation:
In the figure below, EC || AB. Find the length of EC.
Select the best choice from the answers provided.
A.) 12.5
B.) 18
C.) 25
D.) 39.6
Answer:
Letter a)
Step-by-step explanation:
quizlet
Please answer it. I will give brainliest if its correct..
First find the circumference of the circle:
Circumference = 2 x radius x pi
Circumference = 2 x 4 x 3.14 = 25.12 cm
Now arc ML is 100 degrees.
Multiply the circumference by the arc degree/360 ( 360 is a full circle)
25.12 x 100/360 = 6.98 cm
The answer is 6.98 cm
how to solve -x^2-2x+1
Answer:
Common factor
Factor by grouping
Factor by grouping
−
2
−
2
+
1
-x^{2}-2x+1
−x2−2x+1
−
1
(
2
+
2
−
1
)
{\color{#c92786}{-1(x^{2}+2x-1)}}
−1(x2+2x−1)
Solution−
-1(x²+ 2x-1 )
A math teacher has a number cube with faces numbered 1 through 6. He will roll the number cube 400 times. Which of the following ranges contains the best prediction for the number of times the number cube will land with a 1 or a 4 on the top face?
A. 30-35
B. 65-70
C. 130-135
D. 265-270
Answer:
Step-by-step explanation:
B?
Is pop or country your favorite type of music?
Change This into a neutral question
I NEED HELP it's due today! Giving out BRAINLIEST & 30 POINTS!
~Rules~
a. SHOW WORK/CHECK ANSWER
b. NO FILES/LINKS
c. NO SILLY ANSWER
~Hocus Pocus
Answer:
see below
Step-by-step explanation: 5 20 21 02
There are 5 areas to calculate
Top = LW = (20)(17)
Bottom = LW = (20)(15)
Back = LW = (20)(8)
2 Triangular Ends = One square = LW = (8)(15)
Total Surface Area = (20)(17) + (20)(15) + (20)(8) + (8)(15)
= (20)(17 + 15 + 8) + (8)(15)
= (20)(40) + (8)(15)
= 800 + 120
= 920 ft²
The quality-control manager at a compact flourescent light bulb factory wants to test the claim that the mean life of a large shipment of cfls is equal to 6500 hours. the population standard deviation is 500 hours. a random sample of 50 cfls indicates a sample mean life of 6,700 hours and sample standard deviation is 600 hours.
Critical values, where P(Z > Z) - a and P(t >) - a 2016-1282 20.06-1645 20.02 -1.960 10.10. - 1.299 10.06.45 - 1677 foto - 2010 1.115 pt.
a. At the 0.05 level of significance, is there evidence that the mean life is different from 6,500 hours?
b. Compute the p value and interpret its meaning.
c. Construct a 95% confidence interval estimate of the population mean life of the CFLs.
d. Compare the results of (a) and (c). What conclusions do you reach?
Answer:
a. At the 0.05 level of significance, there is evidence that the mean life is different from 6,500 hours.
b. The p value= ≈ 0.00480 for z- test which is less than 0.05 and H0 is rejected .
The p value= 0.006913 for t- test which is less than 0.05 and H0 is rejected for 49 degrees of freedom.
c. CI [6583.336 ,6816.336]
d. The range of CI [6583.336 ,6816.336] tells that the cfls having a different mean life lie in this range.
Step-by-step explanation:
Population mean = u= 6500 hours.
Population standard deviation = σ=500 hours.
Sample size =n= 50
Sample mean =x`= 6,700 hours
Sample standard deviation=s= 600 hours.
Critical values, where P(Z > Z) =∝ and P(t >) =∝
Z(0.10)=1.282
Z(0.05)=1.645
Z(0.025)=1.960
t(0.01)(49)= 1.299
t(0.05)= 1.677
t(0.025,49)=2.010
Let the null and alternate hypotheses be
H0: u = 6500 against the claim Ha: u ≠ 6500
Applying Z test
Z= x`- u/ s/√n
z= 6700-6500/500/√50
Z= 200/70.7113
z= 2.82=2.82
Applying t test
t= x`- u /s/√n
t= 6700-6500/600/√50
t= 2.82
a. At the 0.05 level of significance, there is evidence that the mean life is different from 6,500 hours.
Yes we reject H0 for z- test as it falls in the critical region,at the 0.05 level of significance, z=2.82 > z∝=1.645
For t test we reject H0 as it falls in the critical region,at the 0.05 level of significance, t=2.82 > t∝=1.677 with n-1 = 50-1 = 49 degrees of freedom.
b. The p value= ≈ 0.00480 for z- test which is less than 0.05 and H0 is rejected .
The p value= 0.006913 for t- test which is less than 0.05 and H0 is rejected for 49 degrees of freedom.
c. The 95 % confidence interval of the population mean life is estimated by
x` ± z∝/2 (σ/√n )
6700± 1.645 (500/√50)
6700±116.336
6583.336 ,6816.336
d. The range of CI [6583.336 ,6816.336] tells that the cfls having a different mean life lie in this range.
help me!!!!!!!!!plzzz
Answer:
B. 1/3
Step-by-step explanation:
Answer:
1/3
Step-by-step explanation:
add all the values 10+14+6=30 since red is 10 divide 10 by 30 so 10/30 simplifying to 1/3.
A computer technician notes that 40% of computers fail because of the hard drive, 20% fail due to the processor, 15% of problems are with the keyboard, and 5% of problems are due to something else. What is the mean of the number of computers he will work on before seeing his first computer that has failed because of the hard drive?
Since there are four categories, the technician can expect 4 computers until one has failed due to the hard drive.
Since 40% is equivalent to Two-fifths, it is expected that Five-halves = 2.5 computers until one has failed due to the hard drive.
Since the highest percentage of failure is due to the hard drive, the technician can expect that the first computer will have failed due to the hard drive. So the expected value is 1.
Since it is more likely that a computer has failed due to some other issue, the technician can expect the first computer to fail due to some other issue, and the second to fail due to the hard drive. So the expected value is 2
Answer:
Answer is b
Step-by-step explanation:
A sphere has a volume of 1 cubic foot. What is the approximate diameter of the sphere?
Answer:
[tex]volume \ of \ sphere = \frac{4}{3} \pi r^3 \\\\1 =\frac{4}{3} \pi r^3\\\\r^ 3 = \frac{3}{4\pi} \\\\r = (\frac{3}{4\pi })^{\frac{1}{3} } \\\\r = 0.62ft\\\\diameter = 2 * 0.62 = 1.24ft[/tex]
Answer:
1.24 ft
Step-by-step explanation:
the volume of sphere = 4/3π.r³ = 1
=> r³ = 3/(4π)= 3/(12.56) = 0.239
r = ³√0.239
r = 0.62
d = 2×0.62 = 1.24 ft
if x varies inversely as y and x=2.5 when y = 40 , find y when x = 2
Answer:
2.5/40=2/y
2.5y=40x2
2.5y=80
y=80/2.5
y=32
a food company can produce 732,291,285crackers per hour. A second food company can produce 732,341,285 crackers per hour.Which company can produce more crackers per hour. explain how you found your answer
Answer:
the second company
Step-by-step explanation:
the second company produces 50,000 more crackers an hour than the first company
PYTHAGOREAN THEOREM !! DONT NEED U TO EXPLAIN JUST GIVE ANSWER DONT HAVE TIME FOR THAT !
Answer:
√14 or 3.74
Step-by-step explanation:
_________________
Answer:
√14 or 3.74
Step-by-step explanation:
x = 3.74
What is the surface area of the solid shown below?
Answer:
[tex]\text{C. }156\:\mathrm{cm^3}[/tex]
Step-by-step explanation:
The surface area of the triangular prism consists of three rectangles and two triangles.
Rectangle One - 5 x 12 = 60 cm^2
Rectangle Two - 4 x 12 = 48 cm^2
Rectangle Three - 3 x 12 = 36 cm^2
Triangles - 2 x 1/2 x 3 x 4 = 12 cm^2
Thus, the total surface area of the solid is [tex]60+48+36+12=\boxed{\text{C. }156\:\mathrm{cm^3}}[/tex]
!!!MAJOR HELP AND NO LINKS AND IF YOU DONT KNOW BUT YOU STILL ANSWER, I WILL REPORT IF YOU SAY SOMETHING THAT IS NOT AN ANSWER!!!
What is the solution to the equation 7.5 minus X =2.8?
Image above
Answer: A
Step-by-step explanation:
4.7+2.8 = 7.5
And
7.5 -4.7 = 2.8
What is the surface of the triangluar prism shown below
Answer: 36 ft^2
Step-by-step explanation: 4x3/2=6. 6x2=12. 3x2=6. 4x2=8. 5x2=10. 12+8+6+10=36
consider the following exam scores from a class of 8 students
55,65,77,79,84,89.91,99
What is the rank of the student that scored a 77 on the exam?
Answer:
rank 6
Step-by-step explanation:
You roll 2 dice and flip a coin. What's the probability of getting two 4's and a tails?
Answer:
2/4
Step-by-step explanation:
In a psychology class, 60 students have a mean score of 96.9 on a test. Then 19 more students take the test and their mean score is 71.3.
What is the mean score of all of these students together? Round to one decimal place.
Help please, and thank you! C:
Answer:83.3
Step-by-step explanation:
y=x+5
please help me with this problem I'm really struggling to answer the question.
Answer:12
Step-by-step explanation:just know i did it and got it right
A stack of 14 cookies is 23.1 centimeters high. How thick is each cookie?
Construct an equation for the expression: 3 less than 2 times a number is 7. Show the solution to the equation and prove your solution to be true through your work.
Answer:
5 x 2 -3 = 7
Step-by-step explanation:
i mean.... thats all
You shot a space capsule into an orbit around the space station.
The total weight of the capsule was 1,330 kilograms. If the devices
on board to regulate speed weighed one fourth as much as the fuel
tank and the power unit weighed one half as much as the fuel tank,
how much did the power unit weigh?
In this word problem, what are you asked to find?
CD
The weight of the power unit
b
The weight of the devices to regulate speed
с
The weight of the capsule
d
The weight of the container
A vehicle owner interested in her vehicle’s fuel economy calculated the gas mileage in miles per gallon (mpg) each time she filled her tank, for several years. Here are the mpg values for a random sample of 20 of these records. Suppose that the standard deviation is known to be σ = 3.5 mpg.
Required:
Find the 95% confidence interval for the mean of gas mileage for this vehicle.
Answer:
The 95% confidence interval for the mean of gas mileage for this vehicle is (S - 1.53, S + 1.53), in which S is the mean of the sample of 20.
Step-by-step explanation:
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1 - 0.95}{2} = 0.025[/tex]
Now, we have to find z in the Ztable as such z has a pvalue of [tex]1 - \alpha[/tex].
That is z with a pvalue of [tex]1 - 0.025 = 0.975[/tex], so Z = 1.96.
Now, find the margin of error M as such
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
[tex]M = 1.96\frac{3.5}{\sqrt{20}} = 1.53[/tex]
The lower end of the interval is the sample mean subtracted by M. So it is S - 1.53.
The upper end of the interval is the sample mean added to M. So it is S + 1.53.
The 95% confidence interval for the mean of gas mileage for this vehicle is (S - 1.53, S + 1.53), in which S is the mean of the sample of 20.
HELPP IMA GIVE YOU 15 POINTS
For which data-generating process would a binomial distribution be an appropriate model?
A.flipping a coin to decide whether test subjects should use their left or right hand
B.randomly choosing a letter of the alphabet to pick the first names of test subjects
C.spinning a three-part spinner to decide whether each trial subject should be a child, an adult, or a senior
D.spinning a four-part spinner to decide whether survey customers should be from eastern, southern, midwestern, or western states
Answer:
A. flipping a coin to decide whether test subjects should use their left or right hand
Step-by-step explanation:
Since a coin has two outputs: heads or tails, it it has a binomial distribution
4(x+2) help please.
Answer:
4x + 8
Step-by-step explanation:
4(x+2)
4*x + 4*2
4x + 8
[tex] \large\sf \leadsto 4(x + 2)[/tex]
[tex] \large\sf \leadsto 4 \times (x + 2)[/tex]
[tex] \huge\sf \leadsto \pmb {4x + 8}[/tex]
We often deal with weighted means, in which different data values carry different weights in the calculation of the mean. For example, if the final exam counts for 50% of your final grade and 2 midterms each count for 25%, then you must assign weights of 50% and 25% to the final and midterms, respectively, before computing the mean score for the term. Apply the idea of weighted mean in the following exercise.
A student is taking an advanced anatomy class in which the midterm and final exams are worth 30% each and homework is worth 40% Of his final grade. On a 100-point scale, his midterm exam score was 82.5, his homework average score was 91.6, and his final exam score was 88.6.
Required:
a. On a 100-point scale, what is the student's overall average for the class?
b. The student was hoping to get an A in the class, which requires an overall score of 93.5 or higher. Could he have scored high enough on the final exam to get an A in the class?
Answer:
a) The student's overall average for the class is 87.97.
b) He would need a score above 100 to get an A, which means that he could not have scored high enough on the final exam to get an A in the class.
Step-by-step explanation:
Weighed average:
To solve this question, we find the student's weighed average, multiplying each of his grade by his weights.
Grades and weights:
Scored 82.5 on the midterm, worth 30%.
Scored 88.6 on the final exam, worth 30%.
Scored 91.6 on the homework, worth 40%.
a. On a 100-point scale, what is the student's overall average for the class?
Multiplying each grade by it's weight:
[tex]A = 82.5*0.3 + 88.6*0.3 + 91.6*0.4 = 87.97[/tex]
The student's overall average for the class is 87.97.
b. The student was hoping to get an A in the class, which requires an overall score of 93.5 or higher. Could he have scored high enough on the final exam to get an A in the class?
Score of x on the final class, and verify that the average could be 93.5 or higher. So
[tex]A = 82.5*0.3 + 88.6*0.3 + 0.4x[/tex]
[tex]A \geq 93.5[/tex]
[tex]82.5*0.3 + 88.6*0.3 + 0.4x \geq 93.5[/tex]
[tex]0.4x \geq 93.5 - (82.5*0.3 + 88.6*0.3)[/tex]
[tex]x \geq \frac{93.5 - (82.5*0.3 + 88.6*0.3)}{0.4}[/tex]
[tex]x \geq 105.425[/tex]
He would need a score above 100 to get an A, which means that he could not have scored high enough on the final exam to get an A in the class.