Answers
Related Questions
Christian randomly selects students from his grade to rate a math test as easy, moderate, or difficult. Of the students he surveyed, 13 said the test was easy, 11 rated it as moderate, and 3 found it difficult. Assuming that all students took the same test, how many of the 162 total students in Christian’s grade would probably rate the test something other than easy?
A.
27
B.
78
C.
84
D.
126
Answers
Answer:
C.
84
Step-by-step explanation:
This question is solved using proportions.
From the sample:
11 + 3 = 14 out of 13 + 11 + 3 = 27 would rate the test something other than easy.
Out of 162:
Applying the rule of three:
14 - 27
x - 162
Applying cross multiplication:
[tex]27x = 14*162[/tex]
[tex]x = \frac{14*162}{27}[/tex]
[tex]x = 84[/tex]
Thus the correct answer is given by option C.
Answer:
I hope this helps
Step-by-step explanation:
look at the image below forr the question plz
Answers
Answer:
[tex]308 \ m^3\\[/tex]
Step-by-step explanation:
The volume of a three-dimensional shape is the amount of space the figure takes up. This can be found by multiplying all of the dimensions of a figure together. In essence, the following formula can be used to find the volume.
[tex]A=l*w*h[/tex]
Where (l) represents the figure's length; (w) is the width: and (h) the height. Substitute the given values into the formula and solve for the volume.
[tex]A=l*w*h[/tex]
[tex]A=7*4*11[/tex]
Simplify,
[tex]A=7*4*11[/tex]
[tex]A=28*11[/tex]
[tex]A=308[/tex]
t 0 2 4 6 8 10
P(t) 0 36 43 47 52 60
Kunyu's family has an above ground swimming pool in the shape of a cylinder, with a radius of 10 feet and a height of 5 feet. The pool contains 1000 cubic feet of water at time t=0. During the time interval 0≤t≤10 hours, water is pumped into the pool at the rate () cubic feet per hour. The table above gives values of () for selected values of . During the same time interval, water is leaking from the pool at the rate of () cubic feet per hour, where ()=18−0.04.
(Note: The volume V of a cylinder with radius r and height h is given by =2ℎ .)
Find the rate at which the volume of water in the pool is increasing at time t=6 hours. How fast is the water level in the pool rising at t=6 hours? Indicate units of measure in both answers.
Answers
Answer:
a. 24.12 ft³/hr b. 0.0768 ft/hr
Step-by-step explanation:
a. Find the rate at which the volume of water in the pool is increasing at time t=6 hours.
The net rate of change of volume of the cylinder dV/dt = volume flow rate in - volume flow rate out
Since volume flow rate in = P(t) and volume flow rate out = R(t),
dV/dt = P(t) - R(t)
[tex]\frac{dV}{dt} = P(t) - 18e^{0.04t}[/tex]
We need to find the rate of change of volume when t = 6.
From the table when t = 6, P(6) = 47 ft³/hr
Also, substituting t = 6 into R(t), we have R(6)
[tex]\frac{dV}{dt} = P(t) - 18e^{0.04t}[/tex]
[tex]\frac{dV}{dt} = 47 - 18e^{0.04X6}\\\frac{dV}{dt} = 47 - 18e^{0.24}\\\frac{dV}{dt} = 47 - 18 X 1.27125\\\frac{dV}{dt} = 47 - 22.882\\\frac{dV}{dt} = 24.118 ft^{3}/hr[/tex]
dV/dt ≅ 24.12 ft³/hr
So, the rate at which the water level in the pool is increasing at t = 6 hours is 24.12 ft³/hr
b. How fast is the water level in the pool rising at t=6 hours?
Since the a rate at which the water level is rising is dV/dt and the volume of the cylinder is V = πr²h where r = radius of cylinder = 10 ft and h = height of cylinder = 5 feet
dV/dt = d(πr²h)/dt = πr²dh/dt since the radius is constant and dh/dt is the rate at which the water level is rising.
So, dV/dt = πr²dh/dt
dh/dt = dV/dt ÷ πr²
Since dV/dt = 24.12 ft³/hr and r = 10 ft,
Substituting the values of the variables into the equation, we have that
dh/dt = dV/dt ÷ πr²
dh/dt = 24.12 ft³/hr ÷ π(10 ft)²
dh/dt = 24.12 ft³/hr ÷ 100π ft²
dh/dt = 0.2412 ft³/hr ÷ π ft²
dh/dt = 0.2412 ft³/hr
dh/dt = 0.0768 ft/hr
So, the arate at which the water level is rising at t = 6 hours is 0.0768 ft/hr
What effect will replacing x with (x−4) have on the graph of the equation y=(x−3)2 y = ( x − 3 ) 2 ?
Answers
Answer:
y"= 2 wich is positive
Step-by-step explanation:
Step-by-step explanation:
Our equation is: y=(x-3)²
x should be replaced by x-4
y=(x-3)²
y=[(x-4)-3]²
y=(x-4-3)²
y=(x-7)²
The graph is still a parabola but with a different vertex
The vertex here is :
y= (x-7)²
y= x²-14x-49
y'= 2x-14
solve y'=0
2x-14=0
2x=14
x=7
You can easily find it without derivating by dividing -14 by -2
since: x²-14x-49
a=1 b= -14 c=-49
-b/2a = 14/2 = 7
the image of 7 is:
y=(7-7)² = 0
so the coordinates of the new vertex are (7,0) and it's a maximum
since y">0
y'= 2x-14
y"= 2 wich is positive
Find two consecutive even numbers whose sum is 758.
Answers
Answer:
378 and 380
Step-by-step explanation:
The two even consecutive numbers that add up to 758 are going to be very close to half of 758. This is because two half of 758 are going to be the most similar addends of 758. This is important because the answers will be consecutive and therefore, must also be very similar. To solve, first, divide 758 by 2. This is 379, which is not an even number. So, to find the needed addends subtract and add 1 to 379. Both of these will be even and consecutive. These two numbers are 378 and 380. Then, to check you, can add them and see that they do sum 758.
Answer:
Step-by-step explanation:
Let the first number = x
Let the second number = x + 2
x + x + 2 = 758 Collect like terms
2x + 2 = 758 Subtract 2
2x = 758 - 2 Combine
2x = 756 Divide by 2
2x/2 = 756/2
x = 378
The first number is 378
The second number 380
If your teacher is really fussy, you can do it this way.
Let the first number = 2x
Let the second number = 2x + 2
The reason for this is to guarantee that both numbers were even to start with.
2x + 2x+2 = 758 Combine like terms
4x + 2 = 758 Subtract 2
4x = 756 Divide by 4
x = 756/4
x = 189
Therefore 2x = 378
2x + 2 = 380 Just as before.
The work of a student to solve a set of equations is shown:
Equation A: y = 15 − 2z
Equation B: 2y = 3 − 4z
Step 1: −2(y) = −2(15 − 2z) [Equation A is multiplied by −2.]
2y = 3 − 4z [Equation B]
Step 2: −2y = 15 − 2z [Equation A in Step 1 is simplified.]
2y = 3 − 4z [Equation B]
Step 3: 0 = 18 − 6z [Equations in Step 2 are added.]
Step 4: 6z = 18
Step 5: z = 3
In which step did the student first make an error?
Step1
Step 2
Step 3
Step 4
Answers
Step 2
−2y = 15 − 2z
should be
−2y = -30 + 4a
Find f(2) given f(x) = -3x^2 + 2x+11
Answers
Answer:
Answer:f(2)=-3(2)^2+2*2+11
Answer:f(2)=-3(2)^2+2*2+11 =-3*4+4+11
Answer:f(2)=-3(2)^2+2*2+11 =-3*4+4+11 =-12+4+11
Answer:f(2)=-3(2)^2+2*2+11 =-3*4+4+11 =-12+4+11 =3
hence, f(2)=3
If f(x)=-4x-5 and g(x)=3-x whats is g(-4)+f(1)
Answers
Answer: -2
Step-by-step explanation:
g(-4) = 3 - (-4) = 3 + 4 = 7f(1) = -4(1) - 5 = -4 - 5 = -9g(-4) + f(1) = 7 + (-9) = 7 - 9 = -2
Which fraction is greater than the fraction represented by the model?
HURRY PLS IM BEING TIMED!!!!
Answers
Answer:
7/16
Step-by-step explanation:
7/16>3/8
It would be 7/16 because 3/8 is what is being shown. If you make them both have a common denominator then it would be 6/16.
Find the length of side
x
x in simplest radical form with a rational denominator.
Thanks In advance.
Answers
Answer:
Sorry I dont really understand wish I could help:(
Step-by-step explanation:
Answer:
[tex]\sqrt{10}[/tex]
[tex]\sqrt{5 } ^{2} + \sqrt{5 } ^{2} = x^{2}[/tex]
[tex]x^{2} =10[/tex]
Step-by-step explanation:
The hypotenuse of a right triangle is two more than the length of one of its legs. Find the side lengths of the right triangle given the perimeter= 60 and it's area= 120
Answers
9514 1404 393
Answer:
10 and 24
Step-by-step explanation:
We know that some of the Pythagorean triples that appear in math problems are (3, 4, 5), (5, 12, 13), (7, 24, 25), (8, 15, 17).
These have (perimeter, area) values of (12, 6), (30, 30), (56, 84), (40, 60).
For some scale factor n, we want (p·n, a·n²) = (60, 120). Of the triangles listed, we see that the (5, 12, 13) triangle scaled by n=2 will satisfy the problem requirements. (30·2, 30·2²) = (60, 120)
The side lengths are 10 and 24.
__
Check
For the side lengths we found, the perimeter is 10+24+26 = 60; the area is 1/2(10)(24) = 120. The hypotenuse is 2×13 = 26 = 24+2.
__
In the attached, one side is x, the other is y. The hypotenuse is (x+2). The square root equation comes from ...
x² +y² = (x+2)² ⇒ y² = (x² +4x +4) -x² ⇒ y² = 4x +4 = 4(x +1)
_____
Additional comment
The graph shows the solution of the various constraints. At least, the combination of constraints will give a quadratic equation in x. They can be combined in a way that gives a cubic equation in x. Either way, we prefer the graphical or "guess and check" approach (above) as being easier to do.
Using the third equation in the attachment to write an expression for y, we have ...
y = 58 -2x
Substituting that into the second equation gives ...
(x(58 -2x)/2 = 120
29x -x² = 120
x² -29x +120 = 0
(x -5)(x -24) = 0 . . . . x = 5 or 24.
The root x=5 is a legitimate solution to the pair of equations we chose to solve. The line y=58-2x intersects the hyperbola xy/2 = 120 in two places. However, (x, y) = (5, 48) does not satisfy the hypotenuse requirement that x+2 > y.
Use the diagram to answer the question below.
Name a point not on line AC
Answers
Answer:
It can be the point E or the point D
I need help guys thanks so much
Answers
Answer:
A. 243
Step-by-step explanation:
[tex] 81^\frac{5}{4} = (3^4)^\frac{5}{4} = 3^{4 \times \frac{5}{4}} = 3^5 = 243 [/tex]
Answer: A
I just simplified it to 3^5, and that is also 243.
which decimal is equivalent to 6×100+7×10+4×1/10+8×1/1,000
Answers
The answer is 670.408, because 6x100=600, 7x10=70, 4x1/10 as a decimal is 0.4, 8x1/1,000 as a decimal is 0.008. Then, you add all of those [tex]600+70+0.4+0.008=670.408[/tex].
Which of the following is true because of the Associative Law of Addition?
A. 1000 + 2000 + 6 = 3006
B. (1000) + 2000 + 6 = 1000 + (2000) + 6
C. 1000 + 2000 + 6 = 2000 + 1000 + 6
D. 1000 + (2000 + 6) = (1000 + 2000) + 6
Answers
Answer:
d part is correct because in associative property the brackets and the numbers CAN be shifted
A rectangular window is 48 in long and 36 in wide. Lisa
would like to buy a screen for the window. The cost of
the screen is based on the number of square feet the
screen is. Use the facts to find the area of the window in
square feet.
Conversion facts for length
1 foot (ft) 12 inches (in)
1 yard (yd) = 3 feet (ft)
1 yard (yd) = 36 inches (in)
2
Х
$
?
Answers
[tex]\\ \sf\longmapsto Area=Length\times Breadth[/tex]
[tex]\\ \sf\longmapsto Area=48(36)[/tex]
[tex]\\ \sf\longmapsto Area=1728in^2[/tex]
[tex]\\ \sf\longmapsto Area=144ft^2[/tex]
[tex]\\ \sf\longmapsto Area=48yard^2[/tex]
How tall is the table?
Answers
Answer:
too complex:<
Step-by-step explanation:
120cm+120cm=240cm (2 squirrels + 2 air spaces)
90cm+90cm=180cm (2 rats + 2 air spaces)
240cm-180cm=(2 squirrels + 2 air spaces) - (2 rats + 2 air spaces)
=2 squirrels + 2 air spaces - 2 rats - 2 air spaces
=2 squirrels - 2 rats
=60cm
1 squirrel - 1 rat = 60cm divided by 2
= 30cm
120cm + 90cm = squirrel + air space + rat + air space
= 210cm
I've no idea!! This qn is too challenging!!
But i hope the above workings might help you in a way or another:>
The table is 105cm tall.
What is Equation?Two or more expressions with an Equal sign is called as Equation.
Let the table is x
Squirrel is y
Rat is z
From 1st diagram
x+y-z=120...(1)
From 2nd diagram
x+z-y=90...(2)
Add 1 and 2
x+y-z+x+z-y=120+90
2x=210
Divide both sides by 2
x=105
Hence, the table is 105cm tall.
To learn more on Equation:
https://brainly.com/question/10413253
#SPJ2
the point a(2,-5) is reflected over the origin and its image is point b. what are the coordinates of point b
Answers
Answer:
b(-2,-5)
Step-by-step explanation:
write each of the following fraction as equivalent fractions with a denominator of 10 a. 1/2 b. 1/4 c. 3/30 d. 12/30
Answers
9514 1404 393
Answer:
a. 5/10
b. 2.5/10
c. 1/10
d. 4/10
Step-by-step explanation:
To find the numerator, multiply each fraction by 10.
a. (1/2)(10) = 5, so 1/2 = 5/10
b. (1/4)(10) = 2.5, so 1/4 = (2.5)/10 or (5/2)/10
c. (3/30)(10) = 1, so 3/30 = 1/10
d. (12/30)(10) = 4, so 12/30 = 4/10
Write the ratio 4 L : 5.6 L as a fraction in the simplest form with whole numbers in the numerator and denominator
Answers
Answer:
Step-by-step explanation:
It's 5/7
You get that by having a calculator that does that. If you don't then the way to do it is multiply the numerator and denominator by 1.25
4 * 1.25 = 5
5.6 * 1.25 = 7
I really need help with this one
Answers
FG + GH = FH
3x + 4x = 14
7x = 14
14/7 = 2
x= 2
Your help is very much appreciated I will mark brainliest:)
Answers
Answer:
B. Yes. By SSS~
Step-by-step explanation:
From the diagram given, we have the corresponding sides of both triangles as follows:
RQ/KL = 24/20 = 6/5
QP/LM = 18/15 = 6/5
RP/KM = 12/10 = 6/5
From the above, we can see that the ratio of the corresponding side lengths of both triangles are equal. This means that all three sides of one triangle are proportional to all corresponding sides of the other triangle.
The SSS similarity theorem states that if all sides of one triangle are proportional to all corresponding sides of another, then both triangles are similar to each other.
Therefore, ∆KLM ~ ∆RQP by SSS similarity.
Test scores are normally distributed with a mean of 68 and a standard deviation of 12. Find the z – score for a grade of 74. Round your answer to two numbers after the decimal.
Answers
Answer:
gang nem
Step-by-step explanation:
An equal number of juniors and seniors are trying out for six spots in this year's decathlon
team. If the team must consist of four seniors and two juniors, then how many different
possible decathlon teams could result if five juniors try out?
50
55
75
100
Answers
There are 50 different possible debating teams that could be selected as obtained using COMBINATION.
Since there are EQUAL number of juniors and seniors ;
Then we have 5 of each.
Here, the order of arrangement DOES NOT matter, Hence, we use COMBINATION
since the team MUST contain 4 SENIORS and 2 JUNIORS
4 Seniors from 5 = 5C4 = 5
2 Juniors from 5 = 5C2 = 10
Hence, (5C4 * 5C2) = 5 * 10 = 50
Hence, there are 50 different possible debating teams that could be selected.
Learn more about COMBINATION :
https://brainly.com/question/8018593
How many roots does the equation (8/(x^2 - 16) )+ 1 = 1/(x -4) have?
Plz show ALL STEPS
Answers
Answer:
Step-by-step explanation:
I need to know how to find the area and to simplify it
Answers
Area of parallelogram = b × h
Base = x + 7
Height = x + 3
ATQ
Area = (x + 7) ( x + 3)
x² + 3x + 7x + 21
x² + 10x + 21
Answered by Gauthmath must click thanks and mark brainliest
ANSWER PLS!! :DD
Which of the following is not a property of a regular pyramid?
A. lateral faces that are parallel
B. lateral faces that are congruent isosceles triangles
C. lateral edges that are congruent
D. volume of the pyramid is equal to one-third the product of the area of its base and its altitude
Answers
Answer:
a
Step-by-step explanation:
Lateral faces that are parallel is not a property of a regular pyramid. The correct option is A.
What is a regular pyramid?Any pyramid whose base is a regular polygon and whose lateral edges are all of the same lengths is said to be regular.
The properties of a regular pyramid are:-
Lateral faces that are congruent isosceles triangles. Lateral edges that are congruent and the volume of the pyramid is equal to one-third the product of the area of its base and its altitude.
Hence, option A is correct.
To know more about the regular pyramid follow
https://brainly.com/question/12298863
#SPJ2
answer this now please :)
Answers
9514 1404 393
Answer:
E. 384 cu ft
Step-by-step explanation:
The sum of length and width is half the perimeter, so the width is ...
(40/2) -12 = 8 . . . feet
The depth is half that, so is 8/2 = 4 feet.
The volume is ...
V = LWH = (12 ft)(8 ft)(4 ft) = 384 ft³
Which type of triangle will always have at least 1-fold reflectional symmetry?
right triangle
obtuse triangle
acute triangle
isosceles triangle
Answers
Answer:
D. isosceles triangle
Step-by-step explanation:
Ed22
A triangle with at least 1-fold reflectional symmetry is isosceles triangle, option D is correct.
What is Triangle?A triangle is a three-sided polygon that consists of three edges and three vertices.
An isosceles triangle will always have at least 1-fold reflectional symmetry.
This is because an isosceles triangle has two congruent sides and two congruent angles.
If we draw a perpendicular bisector of the base (the side that is not congruent), it will bisect the base and the angle opposite to the base.
This means that the triangle is symmetric with respect to this line of reflection, which is the line of symmetry.
Therefore, the correct answer is isosceles triangle.
To learn more on Triangles click:
https://brainly.com/question/2773823
#SPJ5
Chris is buying new wood flooring for his house. The cost depends on the area of the floors.
Which is the dependent variable, and which is the independent variable?
Answers
Answer:
strong and fexible .
variable
