Answer:
143
Step-by-step explanation:
The interval of interest extends from the mean score (71) to 2 standard deviations above the mean (71+2(6) = 83). The area under the normal distribution curve in this interval can be found using a suitable table, probability app, spreadsheet, or web site. It can also be found using the "empirical rule", which tells you that the 95% of the area is within 2 standard deviations of the mean.
__
Since the curve is symmetrical, and we're only interested in the area above the mean, the empirical rule tells us that 95%/2 = 47.5% of the sample will be in the range of interest.
0.475 × 300 = 142.5 ≈ 143
143 students will have a score between 71 and 83.
__
The attachment shows a calculator output for the same calculation. You will notice it is slightly different from the "empirical rule," which is only an approximation. Either way, we find 143 students have scores in the range.
Suppose that a, b, x and y are real numbers such that ax+by = 1, ax² + by² = 11, ax³ + by³ = 25 and ax⁴ + by⁴ = 83. Find the value of ax⁵ + by⁵.
Answer:
[tex]ax^5+ by^5=241[/tex]
Step-by-step explanation:
Given:
[tex]ax + by = 1[/tex][tex]ax^2+ by^2 = 11[/tex][tex]ax^3+ by^3 = 25[/tex][tex]ax^4+ by^4 = 83[/tex]We can re-write the left sides of the given equations as follows:
[tex]ax^2+ by^2=(ax+by)(x+y)-xy(a+b)[/tex]
[tex]ax^3+ by^3=(ax^2+by^2)(x+y)-xy(ax+by)[/tex]
[tex]ax^4+ by^4=(ax^3+by^3)(x+y)-xy(ax^2+by^2)[/tex]
Therefore, following this pattern:
[tex]ax^5+ by^5=(ax^4+by^4)(x+y)-xy(ax^3+by^3)[/tex]
Use the given values and the expanded expressions to create 2 equations to help find the values of (x+y) and xy:
Equation 1
[tex]ax^3+ by^3=(ax^2+by^2)(x+y)-xy(ax+by)[/tex]
[tex]\implies 25=11(x+y)-xy(1)[/tex]
[tex]\implies 25=11(x+y)-xy[/tex]
Equation 2
[tex]ax^4+ by^4=(ax^3+by^3)(x+y)-xy(ax^2+by^2)[/tex]
[tex]\implies 83=25(x+y)-xy(11)[/tex]
[tex]\implies 83=25(x+y)-11xy[/tex]
Multiply Equation 1 by 11:
[tex]\implies 275=121(x+y)-11xy[/tex]
Then subtract Equation 2 from this to eliminate 11xy and find the value of (x+y):
[tex]\implies 192=96(x+y)[/tex]
[tex]\implies (x+y)=2[/tex]
Multiply Equation 1 by 25:
[tex]\implies 625=275(x+y)-25xy[/tex]
Multiply Equation 2 by 11:
[tex]\implies 913=275(x+y)-121xy[/tex]
Subtract the 2nd from the 1st to eliminate 275(x+y) and find the value of xy:
[tex]\implies 288=-96xy[/tex]
[tex]\implies xy=-3[/tex]
Therefore, we now have:
[tex]ax^4+ by^4 = 83[/tex][tex]ax^3+ by^3 = 25[/tex][tex](x+y)=2[/tex][tex]xy=-3[/tex]Substitute these into the equation for ax⁵ + by⁵ and solve:
[tex]\implies ax^5+ by^5=(ax^4+by^4)(x+y)-xy(ax^3+by^3)[/tex]
[tex]\implies ax^5+ by^5=(83)(2)-(-3)(25)[/tex]
[tex]\implies ax^5+ by^5=166+75[/tex]
[tex]\implies ax^5+ by^5=241[/tex]
A 2-ft vertical post casts a 20-in shadow at the same time a nearby cell phone tower casts a 115-ft shadow. how tall is the cell phone tower?
the cell phone tower is _ ft
The height of the cell phone tower will be 138 feet.
What are ratio and proportion?A ratio is an ordered set of integers a and b expressed as a/b, with b never equaling 0. A proportional is a mathematical expression in which two things are equal.
A 2-ft vertical post casts a 20-in shadow at the same time a nearby cell phone tower casts a 115-ft shadow.
Then the height of the cell phone tower will be
Let x be the height of the cell phone tower.
x / 2 = 115 x 12 / 20
x = 69 x 2
x = 138 feet
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4 x2-5x-6=0 quadratic form
Step-by-step explanation:
[tex]4 {x}^{2} -5x-6=0 [/tex]
Solve using quadratic formula
Solution:
We know that
[tex] \rm \: Quadratic \: Formula = \cfrac{ - b± \sqrt{ {b}^{2} - 4(ac) } }{2a} [/tex]
ATQ,here,
a = 4b = -5c = -6Substitute the values into the quadratic formula.
[Let Quadratic Formula = x][tex]\rm\implies x = \cfrac{5 ± \sqrt{( - 5) {}^{2} - 4 \times (4 \times - 6) } }{2 \times 4} [/tex]
[tex]\rm\implies{x} = \cfrac{5 ± \sqrt{25 - 4 \times (24) } }{2 \times 4} [/tex]
[tex] \implies \rm \: x = \cfrac{5 ± \sqrt{25 - 96} }{8} [/tex]
[tex] \implies \rm \: x = \cfrac{5± \sqrt{121} }{8} [/tex]
[tex] \implies \rm \: x = \cfrac{5± \sqrt{11 \times 11} }{8} [/tex]
[tex] \implies \rm \: \: x = \cfrac{5±11}{8} [/tex]
The answer will be the combination of both solutions[tex]\boxed{x = 2}[/tex]
OR
[tex]x = \boxed{- \cfrac{3}{4}} [/tex]
Write a nuclear formula for 37^Ca
Answer:
37
20
C
a
→
37
19
K
+
0
+
1
e
This equation shows us the parent atom, which is calcium-37. The mass number is written above the atomic number for the atom. The arrow indicates the decay process with the products to the right of the arrow. The products are an atom of potassium-37 and a positron, which is similar to an electron but it carries a charge of +1 instead of a charge of -1. We can see that the transition of a proton to a neutron in positron decay decreases the atomic number of the atom from 20 to 19, but the mass number of 37 remains the same.
Step-by-step explanation:
Answer:
37
20
C
a
→
37
19
K
+
0
+
1
e
Step-by-step explanation:
To properly use the Addition Property of Equality what number would have to be added in the equation, 14 = x - 6?
A -14
B 14
C -6
D 6
Addition Property of Equality is basically a complex way of saying add the same number to both sides. In this problem we are trying to isolate x for it to be by itself so we must deal with -6. Since we have -6 on one side we must use the "Addition Property of Equality" to add 6 to both sides which would cancel out the -6 and add 6 to 14.
Therefore, the option that best fits the description on what number we would have to use to get added in the equation would be option D, 6.
y=-2/5x
a. direct
b. inverse
c. neither
Answer:
a. direct
Step-by-step explanation:
direct variation is y = kx and y = -2/5x is written in direct variation.
The two tables show the number of copies of albums x, y, and z sold in outlets a, b, c, and d of a company. which outlet sold the greatest number of copies of album x in july and august?
Outlet A sold the greatest number of copies of album x in July and August
How to determine the outlet?The tables of values are given as:
July
Album X Album Y Album Z
Outlet A 14 8 6
Outlet B 7 13 4
Outlet C 2 11 1
August
Album X Album Y Album Z
Outlet A 12 14 10
Outlet B 5 12 8
Outlet C 16 12 7
In July, the total sales of album x are:
Outlet A = 14
Outlet B = 7
Outlet C = 2
In August, the total sales of album x are:
Outlet A = 12
Outlet B = 5
Outlet C = 16
Add both sales
A = 14 + 12 = 26
B = 7 + 5 = 12
C = 2 + 16 = 18
26 (in outlet A) is greater than 12 and 18
Hence, outlet A sold the greatest number of copies of album x in July and August
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Answer:
Outlet D
Step-by-step explanation:
they sold 28 of album x
outlet a only sold 26
1 pound is equivalent to ____ grams.
Answer: 453.592 grams
Step-by-step explanation:
I searched it up online. But if you're going to use this to calculate. Use 454 grams.
Answer:
453.592 rounded would be 454* grams witch is equal to 1 pound
Step-by-step explanation:
1 pound is equivalent to __453.592 or just say 454*__ grams.
Had to fix that hehehe
Hope This Helped
What characteristics do all points in Quadrant I share?
A. The x-coordinate is positive and the y-coordinate is positive.
B. The x-coordinate is negative and the y-coordinate is negative.
C. The x-coordinate is positive and y-coordinate is negative.
D. The x-coordinate is negative and y-coordinate is positive.
Answer:
Option A
Step-by-step explanation:
Remember the things.
In Q1
x>0,y>0in Q2
x<0,y>0in Q3
x<0,y<0in Q4
x>0,y<0Answer:
A. The x-coordinate is positive and the y-coordinate is positive.
Step-by-step explanation:
The Cartesian plane is divided into four regions by the x-axis and y-axis.
These regions are called "quadrants".
Quadrant I is the top right region, where x and y coordinates of points are positive.
From here, move in a counterclockwise direction.
Therefore, Quadrant II is the top left region, where the x-coordinate is negative and the y-coordinate is positive.
Quadrant I → (x, y)
Quadrant II → (-x, y)
Quadrant III → (-x, -y)
Quadrant IV → (x, -y)
The simplified ratio of 32/12 is:
Answer:
8/3
Divide both sides by the GCF, 4.
32 ÷ 4 = 8
12 ÷ 4 = 3
Consider function g.
g(x)={(6,-8<=(-2)<-2 ),(0,-2<=(-2)<4),(-4,4<=(-2)<10):}
What are the values of the function when x = -2 and when x = 4?
g(-2) = __
g(4) = __
By evaluating the piecewise function, we get:
g(-2) = 0.
g(4) = 4.
How to evaluate the piecewise function?A piecewise function is a function that behaves differently in different parts of its domain.
Here, we first want to get g(-2). x = -2 belongs to the second domain, then we use that part:
g(-2) = 0.
For x = 4, it belongs to the third domain, then we have:
g(4) = 4.
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PLEASE HELP PLEASE ANSWER QUICKLY IM RATING 5 STAR AND BRAINLIEST IM LIKE BEGGING FOR HELP ON THIS QUESTION PLEASE ⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️
Answer:
See below
Step-by-step explanation:
Sine function would be easiest
in a right triangle sin = opposite leg / hypotenuse
sin 57 = 10.8 / x
then x = 10.8 / sin 57 then x = 12.88 units
Find the value of h(-7) for the function below.
h(x) = 5.7 −19x
A.
0.67
B.
-138.7
C.
-127.3
D.
138.7
The input value of the function h(-7) for h(x) = 5.7 - 19x is -26.6.
How to find the input value of a Function?We are given the function;
h(x) = 5.7 - 19x
Thus;
h(-7) = 5.7 - 19(1.7)
h(-7) = 5.7 - 32.3
h(-7) = -26.6
Thus, we conclude that the input value of the function h(-7) is -26.6.
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what is the distance from (7,0)- (-5,5)
Answer:
[tex]\frac{5}{-12}[/tex]
Step-by-step explanation:
If you use the formula [tex]m = \frac{y2 - y1} {x2 - x1}[/tex] with x1 being 7, y1 being 0, -5 being x2 and 5 being y2, then you can subtract. 5(y2) minus 0(y1) is 5, and -5(x2) minus 7(x1) is -12. The formula would look like this: [tex]m = \frac{5 - 0}{-5 - 7} \frac{5}{-12}[/tex].
(tip: you need to do rise over run, aka y over x, shown as [tex]\frac{y}{x}[/tex] or [tex]\frac{rise}{run}[/tex])
I hope I helped you answer your question, and helped better understand it as well
Please help me with this!
Answer:
sin(4)
Step-by-step explanation:
sin(-184) is the equivalent to sin(4) (degree), positive and acute angle.
The volume of air in a balloon is represented by the function v(r)=4/3 pi ^3, where r is the radius of the balloon, in
inches. The radius of the balloon increases with time, in seconds, by the function r(t) = 1².
Write a composite function that can be used to determine the volume of the balloon after t seconds. Then, select the
two true statements.
can someone do this for me please?! Just the answer pls
Answer:
see the attachment photo!
The measure of angle is 0 is 7pi/4. The measure of its reference angle is ___ °, and tan 0 is ____
Answer: pi/4 and -1
Step-by-step explanation:
I start a walk at 2.47pm. The walk takes 85 minutes. What time does the walk finish?
Answer:
4:12pm
Step-by-step explanation:
85 minutes = 1 hour and 25 minutes
2:47pm + 1 hour 25 minutes = 3:72 pm
72 minutes = 1 hour 12 minutes so add another 1 hour to 3 and the balance is 12 minutes so walk ends at 4:12pm
Another way to look at it is as follows:
After 13 minutes, the time is 2:47 + 0:13 = 3pm
Remaining time left is 85-13 = 72 minutes = 1 hour: 12 minutes. Add that to 3pm and you get 4:12pm
Which expression is modeled by this arrangement of tiles? 40 positive tiles are broken up into 10 groups of 4 positive tiles. 40 divided by (negative 10) 40 divided by 10 40 divided by 40 40 divided by 40
An expression is defined as a set of numbers, variables, and mathematical operations. The correct option is B.
What is an Expression?
In mathematics, an expression is defined as a set of numbers, variables, and mathematical operations formed according to rules dependent on the context.
Given 40 positive tiles are broken up into 10 groups of 4 positive tiles. The expression that represents this situation is 40 divided by 10.
Hence, the correct option is B.
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Answer:
b
Step-by-step explanation:
If f(x )= 3/x-3, what is (fof)(x)?
Answer:
the second option is correct.
Step-by-step explanation:
that is the solution above.
5x- 4y +2z when x= 8,y =3 and z =3
34
Step-by-step explanation:
=5x-4y+2z
=5×8-4×3+2×3
=40-12+6
=46-12
=34
Rewrite the equation in Ax+By=C form.
Use integers for A, B, and C.
y+1=2(x+5)
Step-by-step explanation:
y + 1 = 2(x + 5) = 2x + 10
y - 9 = 2x
2x - y = -9
Which addition does the model below represent?
5 positive tiles and 3 negative tiles.
Any time we have a single positive tile pair up with a single negative tile, those two tiles cancel out.
Three positive tiles and three negative tiles will pair up and cancel out. We're left with two positive tiles only. This represents the number 2.
In other words, 5 + (-3) = 5 - 3 = 2
Which table represents a function?
Answer:
The one on the top left
Step-by-step explanation:
What makes a function, a function is that the x coordinate (x,y), cannot be repeated in the tables. The y coordinate can though.
11.3 9 9 9 7.8 surface area of triangular prism
Answer:
Total area = 187.65 cm^2
Step-by-step explanation:
AREA of a triangle = 1/2 base * height
THREE sides 3 * 1/2 *9 * 11.3 = 152.55 cm^2
Bottom 1/2 * 9 * 7.8 = 35.1 cm^2
total = 187.65 cm^2
Chandler was a caretaker at the state zoo. He noticed that the number of animals adopted by the zoo increased at a constant rate every year since 2010.
Which of the following graphs shows the slowest rate at which the animals in the zoo were adopted?
A.
B.
C.
D.
Is believed that 80% of adults are honest an honesty experiment was conducted on a random sample of 50 adultsit was discovered that 42 of the adults were honestthe researcher would like to know if the data provide convincing evidence that more than 80% of adults are honest are the conditions for inference met? yesthe conditions for inference are met no, the 10% condition is not met no, the large counts condition is not met no, the randomness condition is not met
The first option, “yes, the conditions for inference are met” is correct.
What are population and sample?It is described as a collection of data with the same entity that is linked to a problem. The sample is a subset of the population, yet it is still a part of it.
Lets you're conducting an experiment on the honesty of a random sample of 50 persons. A total of 42 adults were assessed to be trustworthy.
It has to be determined whether the conditions of inference are satisfied.
A) The randomness of the sample.
The sample is given to be randomly selected. So, this condition is satisfied.
B) The number of success and failures must be at least 10.
The success rate is 0.80, and the sample size is 50. As a result, the following conditions must be met:
[tex]\rm n_p\geq 10 \ and \ n\left ( 1-p \right )\geq 10[/tex]
[tex]\rm 50\left ( 0.80 \right )=40 > 10[/tex]
[tex]\rm 50\left ( 1-0.80 \right )=10=10[/tex]
As a result, the sample size is sufficient, and the big numbers requirement is met.
C) 10% condition:
The sample size is modest, at 50 people, and hence represents less than 10% of the population.
As a result, the inference requirements are met.
Thus, the first option “yes, the conditions for inference are met” is correct.
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Frank has $500 in a savings account that earns 2% interest per year. The interest is not compounded. How much interest will Frank earn in 5 years?
Answer:
$50 interest
Step-by-step explanation:
Simple interest formula
I = Prt
where:
I = interested earnedP = principal amountr = interest rate (in decimal form)t = time (in years)Given:
P = $500r = 2% = 0.02t = 5 yearsSubstitute the given values into the formula and solve for I:
⇒ I = 500 · 0.02 · 5
⇒ I = 50
Therefore, Frank will earn $50 interest in 5 years.
Factor out 1/6 out of 1/6x -7/6
Answer:
(x-7)
Step-by-step explanation:
(1/6)*(x-7)= (1/6)x-(7/6)