Answer:
The approximate percentage of lightbulb replacement requests numbering between 54 and 63 is of 49.85%.
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
Approximately 68% of the measures are within 1 standard deviation of the mean.
Approximately 95% of the measures are within 2 standard deviations of the mean.
Approximately 99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean = 54, standard deviation = 3.
What is the approximate percentage of lightbulb replacement requests numbering between 54 and 63?
63 = 54 + 3*3
So between the mean and 3 standard deviations above the mean.
The normal distribution is symmetric, which means that 50% of the values are below the mean and 50% are above.
Of those 50% above, 99.7% are below 63. So
0.5*0.997 = 0.4985
0.4985*100% = 49.85%
The approximate percentage of lightbulb replacement requests numbering between 54 and 63 is of 49.85%.
Plz help. I’m finding surface area. I need the answer in units. Thank you.
Answer:
C. 17 units
Step-by-step explanation:
Surface area of rectangular prism is given as:
A = 2lw + 2lh + 2wh
A = 930 square units
l = 12 units
h = 9 units
w = ? (We're to find the width)
Plug in the value into the formula
930 = 2*12*w + 2*12*9 + 2*w*9
930 = 24w + 216 + 18w
Add like terms
930 - 216 = 42w
714 = 42w
Divide both sides by 42
714/42 = 42w/42
17 = w
w = 17 units
Say you buy halibut at $19 per pound . One portion of seared halibut requires 6 ounces of halibut . How much does the halibut for one portion cost ? Round to the nearest cent .
Answer:
$7.13
Step-by-step explanation:
Given data
Cost of halibut per pound= $19
Let us convert pound to ounces first
1 pound = 16 ounces
Hence 16 ounces will cost $19
6 ounces will cost x
cross multiply we have
x= 19*6/16
x=114/16
x=$7.13
Hence 6 ounces will cost $7.13
PLEASE HELP SOON Find the value of x. Round to the nearest tenth. 27° х 34° 11 X = ? [?] 9 Law of Sines: sin A sin C sin B b a Enter
The picture of the problem has been attached below :
Answer:
13.5
Step-by-step explanation:
Applying the sine rule to solve for x
SinA /a = SinB / b = SinC/ c
Sin 34 / x = Sin 27/11
Cross multiply :
11 * sin34 = x * sin 27
6.1511219 = 0.4539904x
Divide both sides by 0.4539904
6.1511219/0.4539904 = x
13.549 = x
x = 13.5
Find the angle θ between ???? and ???? if ????⋅????=12‖????‖⋅‖????‖. (Use symbolic notation and fractions where needed. Give your answer in terms of π. )
Answer: hello your question is poorly written below is the complete question
Find the angle between and if ⋅=3√2‖‖⋅‖‖.
(Use symbolic notation and fractions where needed. Give your answer in terms of . )
answer :
∅ = π / 6
Step-by-step explanation:
V .W = [tex]\frac{\sqrt{3} }{2} || V ||. ||W||[/tex]
Hence
∅ = cos^-1 ( [tex]\frac{\frac{\sqrt{3} }{2} || V ||. ||W||}{||V||.||W||}[/tex]
∅ = cos^-1 ( [tex]\frac{\sqrt{3} }{2}[/tex] )
∴ ∅ = π / 6
the sum of the first ten terms of an arithmetic progression consisting of positive integers is equal to the sum of the 20th, 21st and 22nd term. If the first term is less than 20, find how many terms are required to give a sum of 960
Answer:
The correct answer is = 15.
Step-by-step explanation:
Formula:
The sum of the first n terms of an arithmetic progression with first term a and constant difference d is
[tex]S_n=\dfrac{n}{2}[2a+(n-1)d[/tex]
using this formula in this problem
Solution:
The sum of the first ten terms is
[tex]S_{10}=\dfrac{10}{2}[2a+(10-1)d[/tex]
[tex]S_{10}=5(2a+9d)[/tex]
The sum of the 20th, 21st, and 22nd terms is three times the 21st term:
[tex]3a_{21}=3(a+(21-1)d)[/tex]
[tex]3a_{21}=3(a+20d)[/tex]
[tex]3a_{21}=3a+60d[/tex]
The problem then tells us
[tex]S_{10}=3a_{21}[/tex]
[tex]10a+45d=3a+60d[/tex]
[tex]7a=15d[/tex]
there are only positive integers and the first term a is less than 20 as given. Since 7 and 15 have no common factor, the only explanation of the requirements is a = 15 and d = 7. So the progression is
then, 15, 22, 29, 36, ...
The problem says to find the number of terms n for which the sum is 960:
putting value in the formula
[tex]30n+7n^{2}-7n=1920\\7n^{2}+23n-1920=0[/tex]
solving quadratic will give n = 15
thus, the correct answer is 15.
4 mangoes and Pears cost $24 while to Mangos in three pears cost $16. Write a pair of simulataneous equations in x and y to represent the information given. State clearly what x and y represent
Answer:
x- cost of mango, y- cost of pear, 4x+4y=24 and 2x+3y=16
Step-by-step explanation:
For this, you first must assign variables. In this case, let's say x is the cost of a mango and y is the cost of a pear.
Therefore the total cost for the first part can be given by 4x+4y=24.(or 4 × the cost of a mango + 4 × the cost of a pear = $24).
Following this method, the second equation can be given by 2x+3y=16.
** building upon this knowledge (extension)**
To solve simultaneous equations, we need like terms. To make like terms, we can multiply the entire second equation by 2. This gives 2 equations of 4x+4y=24 and 4x+6y=32.
We solve this by subtracting one equation from another, giving (4x-4x)+(6y-4y)=(32-24), or 2y=8.
We can divide by 2 to get y=4, meaning a pear costs $4.
By substituting y with 4, we can work out x. 4x+4×4=24, also known as 4x+16=24.
We can subtract 16 to get 4x=8, and divide by 4, giving x=2, or a mango costs $2.
**This content involves writing simultaneous equations, which you may wish to revise. I'm always happy to help!
Yess again pls help!
Tyyy
Please help, been stuck on this for a while.
Answer:its blurry
Step-by-step explanation:
cant see it
Answer:
x = 34.6
Step-by-step explanation:
[tex]x\:=\:\frac{\left(20\cdot \:sin\left(60\right)\right)}{sin\left(30\right)}[/tex]
A teacher is paid an annual salary of $37.165. What is her gross monthly salary.
Answer:
3.01
Step-by-step explanation:
To Find :-
Monthly salary .SOLUTION :-
=> Monthly salary = $ 37.165/12= $ 3.01
The graph shows the distance Liam traveled from school in miles (y) as a function of time in seconds (x). The graph is divided into four segments labeled P, Q, R, and S, respectively.
Graph shows 4 segments. Segment P is a horizontal straight line. Segment Q is a slanting straight line going up. Segment R is a slanting line going up. Segment S is a slanting straight line going down that touches the x-axis.
Which segment shows Liam waiting for a cab? (5 points)
Select one:
a. P
b. Q
c. R
d. S
Answer:
P
Step-by-step explanation:
Since we are looking at an f(x) graph where x is time and y is distance. Any time a graph is sloping we are either moving closer or further from the school. When there is a horizontal line, this means that there is no change in distance, thus Liam is waiting/standing still.
Answer:
a. P
Step-by-step explanation:
i took the test :)
if f(x)=-5^x-4 and g(x)=-3x-2,find (f+g) (x)
Answer: (f-g)(x) = - 5^x + 3x - 2
Step-by-step explanation:
if f(x) = -5^x - 4 and g(x)= - 3x - 2,find (f-g)(x)
(f-g)(x) = -5^x - 4 - (-3x - 2)
(f-g)(x) = -5^x - 4 + 3x + 2
(f-g)(x) = - 5^x + 3x - 2
The following table shows the distribution of people in a tennis tournament, and one
person is to be selected at random.
Find the probability that the selected person is a female.
Express your answer as a decimal, rounded to the nearest hundredth.
Under Age 35
Male 8 Female 18
35 years and older
Male 11 Female18
Answer:
36/55
Step-by-step explanation:
Total 55 persons, total females 36.
The probability that the selected person is a female from the given table is gotten as; 0.65
What is the Probability?
From the given table we see that;
Males under 35 years = 8
Females under 35 years = 18
Males 35 years and older = 11
Females 35 years and older = 18
Thus;
Total number of people = 8 + 18 + 11 + 18
Total people = 55
Thus, probability that the selected person is a female is;
P(female) = (18 + 18)/55
P(female) = 36/55
P(female) = 0.65
Read more about Probability at; https://brainly.com/question/251701
Consider this function. f(x)-3x+3. Which graph represents the inverse of function f?
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Answer:
graph Y
Step-by-step explanation:
The inverse function can be found by solving ...
x = f(y)
x = -3y +3
x -3 = -3y . . . . . subtract 3; next, divide by -3
y = -1/3x +1 . . . . . matches graph Y
_____
Additional comment
Writing the original equation in standard form can help you see its intercepts.
3x +y = 3
3x = 3 ⇒ x = 1 . . . . x-intercept (at y=0)
y = 3 . . . . y-intercept (at x=0)
The inverse function has the x- and y-intercepts swapped, so you're looking for a line through (0, 1) and (3, 0). The lower left graph (Y) is that graph.
what is the solution to the system of equations below 2x - y = 10 and y=1/2 x+5
Answer:
(10, 10 )
Step-by-step explanation:
Given the 2 equations
2x - y = 10 → (1)
y = [tex]\frac{1}{2}[/tex] x + 5 → (2)
Substitute y = [tex]\frac{1}{2}[/tex] x + 5 into (1)
2x - ([tex]\frac{1}{2}[/tex] x + 5) = 10 ← distribute parenthesis on left side by - 1
2x - [tex]\frac{1}{2}[/tex] x - 5 = 10
[tex]\frac{3}{2}[/tex] x - 5 = 10 ( add 5 to both sides )
[tex]\frac{3}{2}[/tex] x = 15 ( multiply both sides by 2 to clear the fraction )
3x = 30 ( divide both sides by 3 )
x = 10
Substitute x = 10 into (2) and evaluate for y
y = [tex]\frac{1}{2}[/tex] (10) + 5 = 5 + 5 = 10
solution is (10, 10 )
Suppose that you are interested in determining the average height of a person in a large city. You begin by collecting the heights of a random sample of 196 people from the city. The average height of your sample is 68 inches, while the standard deviation of the heights in your sample is 7 inches. The standard error of your estimate of the average height in the city is
Answer:
The standard error of your estimate of the average height in the city is 0.5 inches.
Step-by-step explanation:
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
You begin by collecting the heights of a random sample of 196 people from the city.
This means that [tex]n = 196[/tex]
The standard deviation of the heights in your sample is 7 inches.
This means that [tex]\sigma = 7[/tex]
The standard error of your estimate of the average height in the city is
[tex]s = \frac{\sigma}{\sqrt{n}} = \frac{7}{\sqrt{196}} = 0.5[/tex]
The standard error of your estimate of the average height in the city is 0.5 inches.
Round your answer to the nearest hundredth.
3
А
с
?
8
B
HELP!!!
Answer:
Step-by-step explanation:
This appears to be an SSA application of solving the triangle
We have 2 sides, so we will use the law of cosines
The law of cosines defines for a triangle ABC with side a/b/c with corresponding angles A/B/C
a^2 = b^2+c^2 - 2*b*c * (cos A)
this applies to the other 2 sides
first using the pythagorean theorem we find that BC = sqrt(55)
then we substitute all 3 sides into our equation to find angle A
55 = 64 + 9 - 2*8*3* (cos A)
18 = 2*8*3(cos A)
3/8 = (cos A)
and angle A is approximately 68 degrees
Please check if I'm correct
Answer:
67.98°
Step-by-step explanation:
Given 2 sides, you can find the missing angle of a right triangle using basic trig functions.
Since Cos∅=adjacent/ hypotenuse, we can use the adjacent side to the angle, 3 and they hypotenuse, 8 in the ratio by doing 3/8. This is 0.375. Then we use the inverse cosine function to find the angle. This gives 67.98°
Or
Cos∅=0.375
Cos^-1= 67.98
Let v=-9i+j and w=-i-6j find 8v-6w
Answer:
78i+52j
Step-by-step explanation:
8(9i+2j)-6(-i-6j)
72i+16j+6i+36j
=78i+52j
A circle has a circumference of 2cm. Which statement about the circumference and area is true?
A comparison of the area and circumference is not possible since the area cannot be determinec
The numerical values of the circumference and area of the circle are equal.
The numerical value of the circumference is greater than the numerical value of the area.
The numerical value of the circumference is less than the numerical value of the area.
ОО
Answer:
The numerical values of the circumference and area of the circle are equal.
Drag the label to the correct location on the image
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Answer:
-∞ < y ≤ 12
Step-by-step explanation:
The range is the vertical extent of the graph of the function. Here the function values range from -∞ to a maximum of about 12. An appropriate description is ...
-∞ < y ≤ 12
3. university dean of students wishes to estimate the average number of hours students spend doing homework per week. The standard deviation from a previous study is 4 hours. How large a sample must be selected if he wants to be 96% confident of finding whether the true mean differs from the sample mean by 2 hours
Answer:
A sample of 17 must be selected.
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 - 0.96}{2} = 0.02[/tex]
Now, we have to find z in the Z-table as such z has a p-value of [tex]1 - \alpha[/tex].
That is z with a pvalue of [tex]1 - 0.02 = 0.98[/tex], so Z = 2.054.
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.
The standard deviation from a previous study is 4 hours.
This means that [tex]\sigma = 4[/tex]
How large a sample must be selected if he wants to be 96% confident of finding whether the true mean differs from the sample mean by 2 hours?
A sample of n is required.
n is found for M = 2. So
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
[tex]2 = 2.054\frac{4}{\sqrt{n}}[/tex]
[tex]2\sqrt{n} = 2.054*4[/tex]
Simplifying both sides by 2:
[tex]\sqrt{n} = 2.054*2[/tex]
[tex](\sqrt{n})^2 = (2.054*2)^2[/tex]
[tex]n = 16.88[/tex]
Rounding up:
A sample of 17 must be selected.
Need help putting the answer in
Step-by-step explanation:
We can rewrite the given equation as
[tex]x^2 + \frac{1}{5}x - \frac{12}{25} = (x + \frac{4}{5})(x - \frac{3}{5})[/tex]
As a check, let's multiply out the factors:
[tex](x + \frac{4}{5})(x - \frac{3}{5}) = x^2 - \frac{3}{5}x + \frac{4}{5}x - \frac{12}{25}[/tex]
[tex]= x^2 + \frac{1}{5}x - \frac{12}{25}[/tex]
and this is our original equation.
Can someone please help me
Answer:
sorry I can't help you sorry
Answer:
c
Step-by-step explanation:
A reflection in the x- axis of the parent function is - [tex]\sqrt{x}[/tex]
Given f(x) then f(x) + c is a vertical translation of f(x)
• If c > 0 then a shift up of c units
• If c < 0 then a shift down of c units
Here the shift is 3 units up , then
g(x) = - [tex]\sqrt{x}[/tex] + 3
pls help with all the questions
Answer:
Step-by-step explanation:
Since, CD is an altitude, ∠CDB will be a right angle.
m∠CDB = m∠CDA = 90°
By applying triangle sum theorem in ΔABC,
m∠CAB + m∠CBA + m∠ACB = 180°
20° + m∠CBA + 90° = 180°
m∠CBA = 180° - 110°
= 70°
Therefore, m∠CBD = 70°
By applying triangle sum theorem in ΔBCD,
m∠BCD + m∠CDB + m∠DBC = 180°
m∠BCD + 90° + 70° = 180°
m∠BCD + 160° = 180°
m∠BCD = 20°
m∠CAD = m∠A = 20°
m∠ACD = 90° - m∠BCD
= 90° - 20°
m∠ACD = 70°
Is [0,2) is compact in R?
Answer:
no it is not compact in R
A cylinder with radius 3 meters and height 7 meters has its radius tripled. How many times greater is the volume of the larger cylinder than the smaller cylinder?
How many times greater is the volume of the larger cylinder than the smaller cylinder?
Please help :)
Answer:
9x
Step-by-step explanation:
Quick maths, I dont really have an explaination pls give me brainliest ;-;.
The 2010 GSS provides the following statistics for the average years of education for lower-, working-, middle-, and upper-class respondents and their associated standard deviations. Assume that years of education are normally distributed in the population. Mean Standard Deviation N Lower-class 11.61 2.67 123 Working-class 12.80 2.85 697 Middle-class 14.45 3.08 626 Upper-class 15.45 2.98 38 How many years of education correspond to a Z score of +1.2 for upper-class respondents?
Answer:
The answer is "18.087 years".
Step-by-step explanation:
For upper class:
[tex]\mu=15.45 \ years\\\\\alpha=2.98 \ years\\\\[/tex]
[tex]P(Z \leq 1.2)[/tex] from the standard normal distribution on the table:
[tex]P(Z \leq 1.2) =0.8849\\\\x=z_{\alpha}+\mu\\\\[/tex]
[tex]=0.8849 \times 2.98 +15.45\\\\ = 2.637002+15.45 \\\\=18.087 \ \ years\\[/tex]
i’ll give brainliest to the right answer
Answer:
First one , 0.0000805
Step-by-step explanation:
With negative exponents the decimal is moved to the left the amount of the exponent. The spaces are filled with zeros.
With positive exponents the opposite occurs. The decimal moves to the right.
how do you find the slope of -2
what is the approximate value of x in the diagram below?
Answer:
Where is the diagram though..
Step-by-step explanation:
7/3a - 8/5 +4/15a
Simplified
Answer:
13/5a - 8/5
Step-by-step explanation:
= 35/15a + 4/15a - 8/5
= 39/15a - 8/5
= 13/5a - 8/5
The simplified form of the given expression, "7/3a - 8/5 +4/15a" will be 13/5a - 8/5.
What is an expression?It is defined as the combination of constants and variables with mathematical operators.
It is given that the expression is,7/3a - 8/5 +4/15a.
We have to simplify the expression.
We have to apply the arithmetic operation in which we do the addition of numbers, subtraction, multiplication, and division. It has basic four operators that are +, -, ×, and ÷.
=7/3a - 8/5 +4/15a
= 35/15a + 4/15a - 8/5
= 39/15a - 8/5
= 13/5a - 8/5
Thus, the simplified form of the given expression, "7/3a - 8/5 +4/15a" will be 13/5a - 8/5.
Learn more about the expression here:
brainly.com/question/14083225
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