Answer:
He drove there at 60 mph, and he drove back at 36 mph.
Step-by-step explanation:
one way distance = d = 270 miles
average speed on way back = s
average speed on the way there = s + 24
time driving there = t
time driving back = 12 - t
average speed = distance/time
distance = speed * time
going there:
270 = (s + 24)t
270 = st + 24t
going back
270 = s(12 - t)
270 = 12s - st
We have a system of equations:
270 = st + 24t
270 = 12s - st
Solve the first equation for t.
t(s + 24) = 270
t = 270/(s + 24)
Substitute in the second equation.
270 = 12s - s[270/(s + 24)]
270 = 12s - 270s/(s + 24)
Multiply both sides by s + 24.
270s + 6480 = 12s^2 + 288s - 270s
12s^2 - 252s - 6480 = 0
Divide both sides by 12.
s^2 - 21s - 540 = 0
(s - 36)(s + 15) = 0
s = 36 or s = -15
The average speed cannot be negative, so we discard the solution s = -15.
s = 36
s + 24 = 60
Answer: He drove there at 60 mph, and he drove back at 36 mph.
In a large crowd, there are three times as
many men as women. Three people are
chosen at random. Assuming that there are
so many people that choosing three has a
negligible effect on the proportion of men to
women, find the probability that they are
a.all men
b.2 women and 1 man.
Answer:
A. All men
Explanation
The probability of all men = 0.4219 while the probability of 2 women and 1 man = 0.14
How to solve for the probability of menThe question says we have three times as much men as women
The probability it is a man that was chosen = 3/4
The probability of choosing a woman = 1/4
a. The probability that the chosen persons are all men = (3/4)³
= 0.4219
b. The probability of 2 women and 1 man
3 * 0.75 *0.25²
= 0.14
Hence the probabilities are a. 0.4219 and b. 0.14
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Help me please!!! Thanks
Answer:
Cylinder H has the greater volume.
Step-by-step explanation:
Recall that the volume of a cylinder is given by:
[tex]\displaystyle V=\pi r^2h[/tex]
Where r is the radius and h is the height.
Cylinder H has a radius of 4.5 meters and a height of 3 meters. Thus, its volume is:
[tex]\displaystyle \begin{aligned} V&=\pi(4.5)^2(3)\\&=60.75\pi \\&\approx190.8518\text{ m}^3\end{aligned}[/tex]
Cylinder J has a diameter of 7 meters and a height of 4.5 meters. The radius is half the diameter, so Cylinder J's radius is 3.5 meters. Thus, its volume is:
[tex]\displaystyle \begin{aligned}V&=\pi(3.5)^2(4.5)\\&=55.125\pi \\&\approx 173.1803\text{ m}^3\end{aligned}[/tex]
Thus, Cylinder H has the greater volume.
which graph is that one of the inequality shown below?
Answer:
D
Step-by-step explanation:
SI SE EXTRAE UNA BOLITA DE UNA CAJA CERRADA CON UNA ABERTURA EN LA PARTE SUPERIOR DE LA MISMA.¿CUAL ES LA PROBABILIDAD DE EXTRAER UNA BOLITA DE COLOR SECUNDARIO? LA CAJA CONTIENE : TRES BOLAS DE COLOR PRIMARIO (1 BOLA ROJA,1 BOLA AMARILLA, 1 AZUL) DOS DE COLOR SECUNDARIO(1 NARANJA,1VERDE)
Answer:
La probabilidad es P = 0.4
Step-by-step explanation:
Sabemos que la caja tiene:
3 bolas de color primario (1 roja, 1 amarilla, 1 azul)
2 de color secundario (1 verde, 1 naranja)
Como la bola la sacaremos al azar, todas las bolas tienen exactamente la misma probabilidad de salir.
Queremos obtener la probabilidad de sacar una bolita de color secundario.
Esta probabilidad se calculará como el cociente entre el número de bolitas que cumplen este requisito (es decir, ser de color secundario, sabemos que hay dos de esas) y el número total de bolitas en la caja ( son 5)
La probabilidad es:
P = 2/5 = 0.4
Escribiendo esto en porcentaje (solo se lo multiplica por 100%) tenemos:
40%
Es decir, hay un 40% de posibilidades de sacar una bolita de un color secundario.
Celsius to Fahrenheit
Step-by-step explanation:
149......hshdbhdhsbhsjsusvshhs
find the size of each of the unknown angles.
plz solve this question fast as soon as possible with solution.
Answer:
Angle a = 80°, Angle b = 55°, Angle c = 45°, Angle d = 80°
Step-by-step explanation:
To find the measure of Angle a, we add 55 and 45, then subtract the sum from 180.
180 - 100 = 80
Angle a is 80°.
Then, we solve for Angle b. Line segment CD is congruent to Line AB, so Angle b is congruent to 55°.
After that, we find Angle c. Line segment AC is congruent to Line segment BD, so Angle c is congruent to 45°.
Lastly, we solve for Angle d using the same method we used for Angle b and Angle c. Angle d is congruent to Angle a, so it measures 80°.
So, Angle a = 80°, Angle b = 55°, Angle c = 45°, Angle d = 80°.
If an object looks the same
Answer:
I don't understand your question.............!
Step-by-step explanation:
A casserole is removed from a 375oF oven and cools to 190oF after 25 minutes in a room at 68oF. How long (from the time it is a removed from the oven) will it take the casserole to cool to 105oF
Answer:
57.3 minutes
Step-by-step explanation:
We know that the temperature as a function of time of an object is described by the equation:
[tex]T(t) = T_a + (T_0 - Ta)*e^{-k*t}[/tex]
Where:
k is a constant
Tₐ = room temperature = 68°F
T₀ = initial temperature of the object = 375°F
Replacing these in our equation we will get
T(t) = 68°F + (375°F - 68°F)*e^{-k*t} = 68°F + (307°F)*e^{-k*t}
And we know that after 25 minutes, at t = 25min, the temperature of the casserole is 190°F
then:
T(25min) = 190°F = 68°F + (307°F)*e^{-k*25 min}
Now we can solve this for k:
190°F = 68°F + (307°F)*e^{-k*25 min}
190°F - 68°F = (307°F)*e^{-k*25 min}
(122°F)/(307°F) = e^{-k*25 min}
Now we can apply the natural logarithm in both sides:
Ln( 122/307) = Ln(e^{-k*25 min}) = -k*25min
Ln( 122/307)/(-25 min) = k = 0.0369 min^-1
Then the temperature equation is:
T(t) = 68°F + (307°F)*e^{-0.0369 min^-1*t}
Now we want to find the value of t such that:
T(t) = 105°F = 68°F + (307°F)*e^{-0.0369 min^-1*t}
We can solve this in the same way:
105°F - 68°F = (307°F)*e^{-0.0369 min^-1*t}
37°F = (307°F)*e^{-0.0369 min^-1*t}
(37°F)/(307°F) = e^{-0.0369 min^-1*t}
Ln( 37/307) = -0.0369 min^-1*t
Ln( 37/307)/( -0.0369 min^-1 ) = 57.3 min
So after 57.3 minutes, the temperature of the casserrole will be 105°F
Given line segment AB with endpoints A(-1,7) and B(11, -1)
Find the length of AB.
Step-by-step explanation:
some to check if it correct
The length of the line segment AB is 8.48 unit.
What does length mean?The term used for identifying the size of an object or the distance from one point to another is known as length.
The length of the line segment having endpoints A (x1, y1) and B (x2, y2) can be determined using the formula,
[tex]AB=\sqrt{(x_{2} ^{2} -x_{1} ^{2} )+(y_{2} ^{2} - y_{1} ^{2} )}[/tex]
Given that x1 = -1, x2= 11, y1= 7, and y2= -1.
Substituting the given values in the above equation
[tex]AB=\sqrt{(11^{2}-(-1)^2 )+((-1)^2-7^2)}[/tex]
[tex]AB=\sqrt{72} = 8.48[/tex]
Hence, 8.48 unit is the length of line segment AB.
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What is 1/4 in feet?
Answer:
0.25 feet
7.62 centimeters
3 inches
Step-by-step explanation:
Not really a clear question-
Diego runs for 32 seconds at -8. meters per second .what is his finish point?
Answer:
The finishing point 4
Step-by-step explanation:
32/8=4
Let ℤ be the set of all integers and let, (20) 0 = { ∈ ℤ| = 4, for some integer }, 1 = { ∈ ℤ| = 4 + 1, for some integer }, 2 = { ∈ ℤ| = 4 + 2, for some integer }, 3 = { ∈ ℤ| = 4 + 3, for some integer }. Is {0, 1, 2, 3 } a partition of ℤ? Explain your answer.
Answer:
[tex]\{0, 1, 2, 3\}[/tex] is a partition of Z
Step-by-step explanation:
Given
[tex]$$A _ { 0 } = \{n \in \mathbf { Z } | n = 4 k$$,[/tex] for some integer k[tex]\}[/tex]
[tex]$$A _ { 1 } = \{ n \in \mathbf { Z } | n = 4 k + 1$$,[/tex] for some integer k},
[tex]$$A _ { 2 } = { n \in \mathbf { Z } | n = 4 k + 2$$,[/tex] for some integer k},
and
[tex]$$A _ { 3 } = { n \in \mathbf { Z } | n = 4 k + 3$$,[/tex]for some integer k}.
Required
Is [tex]\{0, 1, 2, 3\}[/tex] a partition of Z
Let
[tex]k = 0[/tex]
So:
[tex]$$A _ { 0 } = 4 k[/tex]
[tex]$$A _ { 0 } = 4 k \to $$A _ { 0 } = 4 * 0 = 0[/tex]
[tex]$$A _ { 1 } = 4 k + 1$$,[/tex]
[tex]A _ { 1 } = 4 *0 + 1$$ \to A_1 = 1[/tex]
[tex]A _ { 2 } = 4 k + 2[/tex]
[tex]A _ { 2} = 4 *0 + 2$$ \to A_2 = 2[/tex]
[tex]A _ { 3 } = 4 k + 3[/tex]
[tex]A _ { 3 } = 4 *0 + 3$$ \to A_3 = 3[/tex]
So, we have:
[tex]\{A_0,A_1,A_2,A_3\} = \{0,1,2,3\}[/tex]
Hence:
[tex]\{0, 1, 2, 3\}[/tex] is a partition of Z
For how many integer values of M is M/30 strictly between 1/3 and 3/5?
Answer:
6 possible intergers brainliest me
Answer:
its 7
Step-by-step explanation:
The distance traveled (in meters) by an insect is modeled by the equation d=0.5t where d is the distance traveled in meters and t is the time in minutes. Find the distance traveled in 27.9 minutes.
A. none of these
B. 13.95 meters
C. 55.8 meters
D. 1.395 meters
Answer:
B. 13.95 meters
Step-by-step explanation:
The question is just asking you to talk the amount of time taken, and divide it in half.
d= 0.5(27.9)
Aubrey tiene un nuevo estuche de arte con forma de prisma rectangular. El estuche es de 12 cm por 20 cm por 5cm. Lo único dentro del estuche es un nuevo borrador rosa con las dimensiones que se muestran a continuación.
¿Cual es el volumen del estuche que no ocupa por el borrador?
Respuesta:
720 cm³
Explicación paso a paso:
El volumen de un prisma rectangular viene dado por:
V = largo * ancho * alto
Dimensión de la caja de arte = 12 por 20 por 5
Dimensión del borrador = largo * ancho * alto
Volumen del borrador = 2 por 4 por 0,5
Dimensión del estuche de arte que no contiene borrador:
(12 por 20 por 5) - (2 por 4 por 0,5)
(10 por 16 por 4,5)
Volumen de la caja que no contiene borrador:
10 * 16 * 4,5 = 720 cm³
Describe fully the graph which has equation x2 + y2 = 9
Answer:
The graph is a circle with a radius of 3 and a center of (0,0).
Step-by-step explanation:
Graph
The equation x² + y² = 9 represents a circle with center (0, 0) and radius = 3
What is equation?"It is a mathematical statement which consists of equal (=) symbol between two algebraic statements."
What is graph of a equation?"It is a set of points (x, y) which satisfy given equation."
For given question,
We have been given an equation x² + y² = 9
The graph of above equation as shown below.
We know, the equation of the circle with center (0, 0) and radius 'r' is, x² + y² = r²
We can write given equation as x² + y² = 3²
Comparing given equation with x² + y² = r² we have r = 3 units
The graph of above equation represents a circle with center (0, 0) and radius = 3
Therefore, the equation x² + y² = 9 represents a circle with center (0, 0) and radius = 3
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a set has 62 proper subsets how many elements has it for?
Answer:
6
Step-by-step explanation:
Total number of subsets is given as
[tex] {2}^{n} [/tex]
But the subset of a set consists of the proper subsets, an empty set and the set itself.
Total number of subsets are 64
Therefore,
[tex] {2}^{n} = 64[/tex]
[tex] {2}^{n} = {2}^{6} [/tex]
Comparing both sides
[tex]n = 6[/tex]
WILL GIVE BRAINLIEST
A graph has hours studied on the x-axis and test scores on the y-axis. Points are at (1, 3), (2, 6), (3, 5), (3, 8), (4, 5), (5, 8), (8, 9).
What statements describe this graph? Check all that apply.
The points are scattered.
The points are not connected.
The graph displays a discrete graph.
The graph displays the relationship of test scores to hours studied.
The graph represents the relationship between two sets of data.
Answer:
A,C,D.
Step-by-step explanation:
Answer:
Part A
Group A is a cluster of points with similar property or relationship.
Point B is an outlier. This is the point outside of the common relationship.
Part B
There is a negative tendency. As number of hours spent on computer games increase, the test scores decrease.
Step-by-step explanation:
so basically A, and B
Can someone help me with this math homework please!
Answer:
DOMAIN
input values belong to domainset of values for the independent variable is called the domainRANGE
output values belong to range set of values for the dependant variable is called the range(9-3)+18÷9
show your work
(9-3)+18÷9
= 6+18÷9
= 6+2
= 8
Answer:
8
Step-by-step explanation:
Well, we need to use order of operations. Since there are parenthesis, we solve what is inside that first. So, 9-3=6. We have solved one part of the equation. There are no exponents so division comes next. 18/9=2. Now we are left with 6+2. 6+2=8. Therefore, your final answer is 8.
John had $20. He earned $5, spent $10, earned $5 again, and then spent $3. After this series of earings and expenses, how much money did he owe or have left?
Answer:
It might be $17 for how much he has left.
Step-by-step explanation:
$20+$5-$10+5-$3=$17
[tex] \frac{x}{2} + \frac{6}{x } = 4[/tex]
using quadratic equation....help me if you can
Help please-- Given circle O below, if arc GH and arc HJ are congruent, what is the measure of chord line HJ?
Answer:
the answer is D
Step-by-step explanation:
plz help ASAP with explanation
Answer:
The height of the tank in the picture is:
19.5 cmStep-by-step explanation:
First, to know the height of the tank, we're gonna change the unit of the volume given in liters to cm^3:
1 liter = 1000 cm^3So:
1.2 liters = 1200 cm^3Now, we must calculate the height of the tank that we don't know (the other part that isn't with water), to this, we can use the volume formula clearing the height:
Volume of a cube = long * wide * heightNow, we must clear the height because we know the volume (1200 cm^3):
Height = volume of a cube / (long * wide)
And we replace:
Height = 1200 cm^3 / (12 cm * 8 cm)Height = 1200 cm^3 / (96 cm^2)Height = 12.5 cmRemember this is the height of the empty zone, by this reason, to obtain the height of the whole tank, we must add the height of the zone with water (7 cm) that the exercise give us:
Heigth of the tank = Height empty zone + height zone with waterHeigth of the tank = 12.5 cm + 7 cmHeigth of the tank = 19.5 cmIn this form, we calculate the height of the tank in 19.5 cm.
What is the value of x to the nearest tenth?
A) 9.2
B) 7.2
C) 4.8
D) 12.0
Answer:
B. 7.2
Step-by-step explanation:
radius=24÷2= 12
other line =19.2÷2=9.6 because line from centre bisects chord and is perpendicular to it
Therefore: X²=√ 12²-9.6² ( theorem of Pythagoras)
X=7.2
y4+5y2+9 factorise please help me
[tex]\displaystyle\ y^4 +5y^2+9=(y^2+3)^2-y^2=(y^2-y+3)(y^2+y+3)[/tex]
Answer:
Solution given;
[tex] y^{4}+5y²+9[/tex]
keeping [tex]y^{4} and 9 together [/tex]
[tex]y^{4}+9+5y²[/tex]
[tex](y²)²+3²+5y²[/tex].....[I]
we have
a²+b²=(a+b)²-2ab
or
a²+b²=(a-b)²+2ab
same like that
[tex](y²)²+3²=(y²+3)²-6y² or (y²-3)²+6y²[/tex]
remember that while adding or subtracting the left term 5y² either adding 6y²or subtracting 6y²
should make the term perfect square
while subtracting it makes perfect square
so
we take
(y²)²+3²=(y²+3)²-6y²
again
substituting value of
(y²)²+3² in equation 1 and it becomes
(y²+3)²-6y²+5y²
solve like terms
(y²+3)²-y²
again
we have
a²-b²=(a+b)(a-b)
by using this.
(y²+3+y)(y²+3-y)
rearrange it
(y²+y+3)(y²-y+3) is a required factorisation form.
If (2x - 3) is a factor of mx^2 - 11x - 6, find the other factor.
Answer:
(2x - 3) ^2 - 11x - 6
Step-by-step explanation:
A certain polygon has its vertices at the following points: (1, 1), (1, 8), (8, 1), and (8, 8)
Answer:
Can u explain more pls?
Step-by-step explanation:
Answer:
Square
Step-by-step explanation:
consider the two triangles shown below are the two triangles congruent
Answer: Yes
Step-by-step explanation: Let's first find the missing angle in the second triangle and to find this angle, remember that the sum of the measures of a triangle is 180 degrees so you should find that our missing angle is 67°.
Now, notice that we have two angles and the included side of one triangle
congruent to two angles and the included side of a second triangle.
Therefore, we can say the triangles are congruent by ASA.
The given equation has been solved in the table. Step Statement 1 1 –7n + 11 = -10 2. -7n + 11 – 11 = -10 – 11 3 -7n = -21 4 = = =21 .In -7 -21 __7 5 n = 3 Use the table to complete each statement. In step 2, the In step 4, the property of equality was applied. property of equality was applied.
Answer:
In step 2, the subtraction property of equality was applied
In step 4, the division property of equality was applied
Step-by-step explanation: