Answer:
a. 0.8944 = 89.44% probability that the player functions for at least 8 hr
b. 0.9938 = 99.38% probability that the cassette player works for at most 11 hr
c. z* = 10.024 hr
Step-by-step explanation:
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
Mean value of 9 hr and a standard deviation of 0.8 hr
This means that [tex]\mu = 9, \sigma = 0.8[/tex]
a. What is the probability that the player functions for at least 8 hr?
This is 1 subtracted by the pvalue of Z when X = 8. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{8 - 9}{0.8}[/tex]
[tex]Z = -1.25[/tex]
[tex]Z = -1.25[/tex] has a pvalue of 0.1056
1 - 0.1056 = 0.8944
0.8944 = 89.44% probability that the player functions for at least 8 hr.
b. What is the probability that the cassette player works for at most 11 hr?
This is the pvalue of Z when X = 11. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{11 - 9}{0.8}[/tex]
[tex]Z = 2.5[/tex]
[tex]Z = 2.5[/tex] has a pvalue of 0.9938
0.9938 = 99.38% probability that the cassette player works for at most 11 hr.
c. Find a number z* such that only 10% of all cassette players will function without battery replacement for more than z* hr.
This is the 90th percentile, which is X when Z has a pvalue of 0.9, that is, X when Z = 1.28.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]1.28 = \frac{X - 9}{0.8}[/tex]
[tex]X - 9 = 1.28*0.8[/tex]
[tex]X = 10.024[/tex]
So
z* = 10.024 hr
Rewrite the equation by completing the square.
x2 + 7x + 12 = 0
Answer:
9x²+12=0
Step-by-step explanation:
Madison draws an isosceles triangle with side lengths of 10 inches, and the angle between them of 50°. Can you find the measures of the other angles based on this information? Explain your answer.
S.O.S !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Answer:
120
Step-by-step explanation:
add 50+10=60
then 180-60=120
Pls ASAP it’s due today
Step-by-step explanation:
It's this way.I hope it helped.
Write an expression to describe the sequence below. Use n to represent the position of a
term in the sequence, where n = 1 for the first term.
11, 12, 13, 14, ...
Answer:
n+10
Step-by-step explanation:
This is applicable because if you plug in the numbers it will work for example. -
what sequence is 12 in, it is the second number so n=2
so add 10 to 2 which is 12
So as seen the answer is n+10
thanks and mark me brainliest
When simplifying radical expressions, what combination of factors are you looking for and why?
What is the distance between the points (2, 3) and (5, -4)?
7.6 units
6.3 units
3.7 units
10 units
Answer:
7.6 units
Step-by-step explanation:
d=(5−2)2+(−4−3)2−−−−−−−−−−−−−−−−√
d=(3)2+(−7)2−−−−−−−−−−√
d=9+49−−−−−√
d=5–√8
d=7.615773
I just need brainliest please
Answer:
alright if you give me brianliest on this, when you answer one of my questions ill give you brainliest. brailiest for a brianliest?
Step-by-step explanation:
Answer
Catfishing, In LOl rate 0-10 Im bored
Step-by-step explanation:
What is the solution set for (2x-7)^2=25
The solution set for the quadratic equation (2x - 7)² = 25 is 6 and 1.
What is a quadratic equaton?A quadratic equation is an algebraic expression in the form of variables and constants.
A quadratic equation has two roots as its degree is two.
The solution set for a quadratic equation is the roots of the quadratic equation.
Given, (2x - 7)² = 25.
2x - 7 = ± 5.
2x = ± 5 + 7.
x = (± 5 + 7)/2.
x = 12/2 Or 2/2.
x = 6 or 1.
learn more about quadratic equations here :
https://brainly.com/question/11589380
#SPJ2
What does the point (12,4) represent in this situation?
Answer:
what is the situation?
Step-by-step explanation:
Write an expression equivalent to 2/3 (x-6)
Answer:
2/3x-4
Step-by-step explanation:
2/3*x=2/3x
2/3*6=4
Simplify by combining like terms (3x2-5x- 6x)+(5x2+4x+4)
Step-by-step explanation:
I hope this helps. ans:9x+4
Find the length of the hypotenuse in the figure shown below.
Answer:
it's 13
√144+25=13
good luck
What is the area of 3/4 of a circle?
(With a radius of 2)
Answer: 12.57
Step-by-step explanation: I got u
someone please help on this homework question
Answer:
25%, 40 trees, 50%, 36 trees
PLEASE HELP I WILL GIVE BRAINLIEST!!
Answer:
43.96
Step-by-step explanation:
To find Circumference the formula is
2*3.14*R=C
replace R with your radious which is 7
2*3.14*7=43.96
Rashawn kept a record of how many hours he spent listening to music for 6 days during school vacation and displayed his results in the table below.
On Sunday, Rashawn listened to music for 12 hours. Should he use the mean or median to describe the data for the entire week?
Which statement explains whether the mean or median is the better measure of center?
A. The mean is the better measure because Rashawn listened to music the median number of hours on only 2 days of the week.
B. The mean is the better measure for the entire week because their is no outlier.
C. The median is the better measure because the mean is affected by the outlier.
D. The median is the better measure because almost all of the data points are between 6 and 7.
Answer:
B. The mean is the better measure for the entire week because their is no outlier.
Answer: C The median is the better measure because the mean is affected by the outlier
The function f(3) = 50.000(0.975)", where x represents the underwater
depth in meters, models the intensity of light below the water's surface in lumens per
square meter. What is the intensity of light 200 meters below the surface
9514 1404 393
Answer:
316 lumens/m²
Step-by-step explanation:
We assume your intensity function is ...
f(x) = 50,000(0.975^x) . . . . x meters below the surface
__
Use 200 for x and do the arithmetic.
f(200) = 50,000(0.975^200) ≈ 316 . . . . lumens/m²
2(x-5) -6=-18 please help asap
Answer:
x = -1
Step-by-step explanation:
2 (x - 5) -6 = - 18
2 (x - 5) = - 12
x - 5 = - 6
x = - 1
Answer:
x=-1
is what the answer is to X
What is the least common denominator of 11/14 and 11/15
Answer:
210
Step-by-step explanation:
210 is the least common multiple of 14 and 15
need help fast thanks
Answer: AOS: x =3 Vertex at (3,2)
Step-by-step explanation:
Two years ago, the average number of customers in your all of your company's stores per week was 3173 customers. This figure had increased 6% over the previous two years. Assume that you are doing a current study to test the claim that the mean weekly number of customers is different than it was two years ago. Assume a population standard deviation of 1,550 customers. Suppose you look at a random sample of 73 stores and find an average weekly customer total of 3,391. You wish to test the claim stated above at the 0.10 level. Run the appropriate hypothesis test.
Required:
Write ONLY the conclusion to your hypothesis test.
Answer:
Accept the null hypothesis
Step-by-step explanation:
Two years ago, the average number of customers in your all of your company's stores per week was 3173 customers. Assume that you are doing a current study to test the claim that the mean weekly number of customers is different than it was two years ago.
The null hypothesis is:
[tex]H_{0} = 3173[/tex]
The alternate hypothesis is:
[tex]H_{A} \neq 3173[/tex]
The test statistic is:
[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, [tex]\sigma[/tex] is the standard deviation and n is the size of the sample.
Due to our test, we have that [tex]\mu = 3173[/tex]
Assume a population standard deviation of 1,550 customers.
This means that [tex]\sigma = 1550[/tex]
Suppose you look at a random sample of 73 stores and find an average weekly customer total of 3,391.
This means that [tex]n = 73, X = 3391[/tex]
Test statistic:
[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
[tex]z = \frac{3391 - 3173}{\frac{1550}{\sqrt{73}}}[/tex]
[tex]z = 1.24[/tex]
p-value:
Since we are testing if the mean is different of a value, and the z-score is positive, the pvalue is 2 multiplied by 1 subtracted by the pvalue of z = 1.24.
z = 1.24 has a pvalue of 0.9251
2*(1 - 0.9251) = 2*0.0749 = 0.1498
0.1498 > 0.1, which means that we accept the null hypothesis, that is, that the mean weekly number of customers is equal to what it was two years ago at the 0.1 level of significance.
Complete the tables of values.
5)
44
-1
- 1
4
O
d
0
d
2
b
2.
*
4
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4.
d
b =
d at
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after 3 new students joined, the class had 26 students. which equations can be used to find n, the number of students in class before the 3 new students joined?
Answer:
23 were there
Step-by-step explanation:
26 - 3 = 25
helped
A: 3n =26
B: n - 3 =26
C: n + 3 =26
D n/3 =26
0.5 divided by 0.05 plz show work
Answer:
Step-by-step explanation:
Answer: 10
working below!
Each unit on the grid below represents 1 cm. Find the height of the arrow on a rescaled drawing using the scale 1cm= 0.5 m.
Answer:
8
Step-by-step explanation:
add them duh
Shade the fraction circles to represent each mixed number.. 1 3/5 +2 2/5 equals
plz is this correct
?
Answer:
It's 3 and 177.
Step-by-step explanation:
Let the angle be x°. Then its supplementary is 59x°.
We know,
x+ 59x=180
or, x = 3°
and another angle, 59x°= 177°
Plot 7 + 3i in the complex plane.
Answer:
See attached image
Step-by-step explanation:
In the complex plane, the x-axis represents real numbers and the y-axis represents imaginary numbers.
there are 3 consecutive even integers. three times the smallest is twice the largest. what are the integers
100 poi's SOLVE FAST PLZ AND I WILL GIVE BRAINLEITS I PORMISE
Answer:
8,10,12
Step-by-step explanation:
Answer:
integer 1 = 8
integer 2 = x+2 = 8+2 = 10
integer 3 = x+4 = 8+4 = 12
Step-by-step explanation:
integer 1 = x , smallest
integer 2 = y , x+12
integer 3 = z , largest, x+4
three times the smallest is twice the largest.
3 (x) = 2 (x+4)
solve for x:
3x = 2x + 8
3x-2x = 8
x = 8
Replacing:
integer 1 = 8
integer 2 = x+2 = 8+2 = 10
integer 3 = x+4 = 8+4 = 12
Find the equation of the line with slope m=−12 that contains the point (2,−4).
Answer:
y=-12x+20
Step-by-step explanation:
-4=-12(2) +b
-4=24+b
(add 24 both sides)
20=b
slope: -12
y intercept: (0,20)
Answer:
y + 4 = -12(x - 2)
Step-by-step explanation:
Use the point-slope formula for the equation of a straight line:
y - k = m(x - h)
Here m = -12, h = 2 and k = -4, and so we have:
y + 4 = -12(x - 2)