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
[tex]\text{Solve the system of equations:}\\\\\left \{ {{y=3x+5} \atop {y=-4x+7}} \right.\\\\\text{Thank you.}[/tex]
Hi there!
»»————- ★ ————-««
I believe your answer is:
(0.286, 5.587)
»»————- ★ ————-««
Here’s why:
⸻⸻⸻⸻
I have graphed the two equations in a program. When graphed, the lines intersect at point (0.286, 5.587). See the graph attached.⸻⸻⸻⸻
»»————- ★ ————-««
Hope this helps you. I apologize if it’s incorrect.
Can someone help with the ones I haven’t answer
Answer:
Step-by-step explanation:
[tex]5) 5\frac{11}{12}+3\frac{5}{6}=5+\frac{11}{12}+3+\frac{5}{6}\\\\ =8 +\frac{11}{12}+\frac{5*2}{6*2}\\\\= 8 +\frac{11}{12}+\frac{10}{12}\\\\=8 +\frac{11+10}{12}\\\\= 8+\frac{21}{12}\\\\=8+ 1\frac{9}{12}\\\\= 9\frac{9}{12}[/tex]
The temperature of a cup of coffee varies according to Newton's Law of Cooling: -"dT/dt=k(T-A), where is the temperature of the coffee, A is the room temperature, and k is a positive
constant. If the coffee cools from 100°C to 90°C in 1 minute at a room temperature of 25*C, find the temperature, to the nearest degree Celsius of the coffee after 4 minutes,
74
67
60
42
Answer:
B) 67°C.
Step-by-step explanation:
Newton's Law of Cooling is given by:
[tex]\displaystyle \frac{dT}{dt}=k(T-A)[/tex]
Where T is the temperature of the coffee, A is the room temperature, and k is a positive constant.
We are given that the coffee cools from 100°C to 90°C in one minute at a room temperature A of 25°C.
And we want to find the temperature of the coffee after four minutes.
First, solve the differential equation. Multiply both sides by dt and divide both sides by (T - A). Hence:
[tex]\displaystyle \frac{dT}{T-A}=k\, dt[/tex]
Take the integral of both sides:
[tex]\displaystyle \int \frac{dT}{T-A}=\int k\, dt[/tex]
Integrate:
[tex]\displaystyle \ln\left|T-A\right| = kt+C[/tex]
Raise both sides to e:
[tex]|T-A|=e^{kt+C}=Ce^{kt}[/tex]
The temperature of the coffee T will always be greater than or equal to the room temperature A. Thus, we can remove the absolute value:
[tex]\displaystyle T=Ce^{kt}+A[/tex]
We are given that A = 25. Hence:
[tex]\displaystyle T=Ce^{kt}+25[/tex]
Since the coffee cools from 100°C to 90°C, the initial temperature of the coffee was 100°C. Thus, when t = 0,T = 100:
[tex]100=Ce^{k(0)}+25\Rightarrow C=75[/tex]
Hence:
[tex]T=75e^{kt}+25[/tex]
We are given that the coffee cools from 100°C to 90°C after one minute at a room temperature of 25°C.
So, T = 90 given that t = 1. Substitute:
[tex]90=75e^{k(1)}+25[/tex]
Solve for k:
[tex]\displaystyle e^k=\frac{13}{15}\Rightarrow k=\ln\left(\frac{13}{15}\right)[/tex]
Therefore:
[tex]\displaystyle T=75e^{\ln({}^{13}\! /\!{}_{15})t}+25[/tex]
Then after four minutes, the temperature of the coffee will be:
[tex]\displaystyle \begin{aligned} \displaystyle T&=75e^{\ln({}^{13}\! /\!{}_{15})(4)}+25\\\\&\approx 67^\circ\text{C}\end{aligned}[/tex]
Hence, our answer is B.
PLS HELP ASAP!
which of the follwing expressions is equvialent to:
*image below*
Answer:
A
Step-by-step explanation:
simplify equation A
then you will get same as the expression above
Elana runs for 28 seconds and finishes at 250 meters .what is her velocity
Answer:
8.9m/s
Step-by-step explanation:
Time= 28s
Displacement= 250m
Velocity=?
Velocity (v) = displacement (d)/ Time (t)
V= 250/28
V=8.9m/s
OR YOU CAN APPROXIMATE IT
V=8.928
YOU CAN APPROXIMATE IT TO
V=8.93m/s
if f(x)=x^2-11 for what values of x is f(x) < 25
Answer: D
Step-by-step explanation:
5²-11=14
6^2-11= 25
14>25
as the question asks for something lower than 25 not lower/equal to the answer is D.
The range of values for which f(x) < 25 are -6 < x < 6. The correct answer choice is e).
To find the values of x for which f(x) < 25, we substitute the expression for f(x) into the inequality and solve for x.
Given f(x) = x² - 11, we need to find the values of x that make f(x) less than 25.
x² - 11 < 25
Adding 11 to both sides, we have:
x² < 36
To determine the values of x that satisfy this inequality, we take the square root of both sides. Since the square root of a number can be positive or negative, we consider both positive and negative solutions.
x < √36
x > -√36
Simplifying, we get:
x < 6
x > -6
Therefore, the correct answer choice is e) -6 < x < 6, as it represents the range of values for which f(x) < 25. This means that x can take any value between -6 and 6 (excluding -6 and 6) for the inequality to hold true.
To learn more about function click on,
https://brainly.com/question/32772416
#SPJ2
What is the number that fills in for AD?
the answer is in the picture
If x = 3 and y = 5, work out the value of
b) 2x2 + 3y2
Answer:
42
Step-by-step explanation:
2*3*2+3*5*2=12+30=42
Answer:
[tex]93[/tex]
Step-by-step explanation:
Given:
If [tex]x=3[/tex] & [tex]y=5[/tex], find [tex]2x^2+3y^2[/tex]
Solution:
Replace 3 with x and 4 with y:
[tex]2(3)^2+3(5)^2[/tex]
[tex]=2(9)+3(25)[/tex]
[tex]=18+75[/tex]
[tex]=93[/tex]
Can someone help me?
Answer:
C
Step-by-step explanation:
its asking for y, on the graph, the line is placed on point 4
3. Length of a cubic container is 20 cm .A cube with a length of edges 5 cm will be used to take some water from a water barrel. Determine the maximum number of cubes that need to use to fill the container with water.
We have l = 20 * 20 * 20 = 8000 cm3
One cube will have l = 5 * 5 * 5 = 125 cm3
-> The maximum number of cubes that need to use to fill the container with water is 8000 / 125 = 64
what is the value of x?
Answer:
x°=70°{ vertically opposite angle are equal}hope it helps.stay safe healthy and happy..We know that,
Vertically opposite angles are equal,
So, x° = 70°
=> x = 70
8.
Out of total population of 50,000, only 28,000 read Newspaper and 23,000 read
magazines while 4,000 read both. How many of them do not read any paper ?
the answer is in the picture
What is the circumference of D if the length of EF is 9 cm?
Answer:
It should be B, 180 cm
Step-by-step explanation:
x = circumference of circle D
18/360 = 9/x
9*360 = 18x
9*360/18 = x
x = 180
Use two unit multipliers to convert 36 inches to miles.
Answer:
36 inches = 0.000568182 miles
A line with a slope of 3 passes through the point (-1, 2).
Write an equation for this line in point-slope form.
Answer:
Step-by-step explanation:
Slope = m = 3
(x₁ , y₁) = (-1 , 2)
Point slope form: y - y₁ = m(x - x₁)
y - 2 = 3(x - [-1] )
y - 2 = 3(x + 1)
y - 2 = 3*x + 3*1
y - 2 = 3x + 3
y = 3x + 3 + 2
y = 3x + 5
PLEASE HELPP ILL GIVE 20 POINTS
Answer:
C=20
Step-by-step explanation:
Determine the period.
N
10
Hello,
f(x+5)=f(x)
Periode is 5
Answer:
It's 4 on acellus, not 5 :)
Step-by-step explanation:
There are 35 times as many students at Wow University as teachers. When all the students and
teachers are seated in the 8544 seat auditorium, 12 seats are empty. How many students attend
Wow University?
Given:
There are 35 times as many students at Wow University as teachers.
When all the students and teachers are seated in the 8544 seat auditorium, 12 seats are empty.
To find:
The total number of students.
Solution:
Let x be the number of teachers at Wow University. So, the number of student is :
[tex]35\times x=35x[/tex]
When all the students and teachers are seated in the 8544 seat auditorium, 12 seats are empty.
[tex]x+35x=8544-12[/tex]
[tex]36x=8532[/tex]
[tex]x=\dfrac{8532}{36}[/tex]
[tex]x=237[/tex]
The number of total students is:
[tex]35x=35(237)[/tex]
[tex]35x=8295[/tex]
Therefore, the total number of students is 8295.
Find the inverse mapping of x 2x +1
Lim x->-5(((1)/(5)+(1)/(x))/(10+2x))=
correct answer 1/10x = -1/50
explain:
Given:
The limit problem is:
[tex]lim_{x\to -5}\dfrac{\dfrac{1}{5}+\dfrac{1}{x}}{10+2x}[/tex]
To find:
The value of the given limit problem.
Solution:
We have,
[tex]lim_{x\to -5}\dfrac{\dfrac{1}{5}+\dfrac{1}{x}}{10+2x}[/tex]
It can be written as:
[tex]=lim_{x\to -5}\dfrac{\dfrac{x+5}{5x}}{2(5+x)}[/tex]
[tex]=lim_{x\to -5}\dfrac{x+5}{5x}\times \dfrac{1}{2(5+x)}[/tex]
[tex]=lim_{x\to -5}\dfrac{1}{5x\times 2}[/tex]
[tex]=lim_{x\to -5}\dfrac{1}{10x}[/tex]
Applying limit, we get
[tex]lim_{x\to -5}\dfrac{1}{10x}=\dfrac{1}{10(-5)}[/tex]
[tex]lim_{x\to -5}\dfrac{1}{10x}=\dfrac{1}{-50}[/tex]
Therefore, the value of given limit problem is [tex]-\dfrac{1}{50}[/tex].
14,523 to 16,489.
What is the percent increase in the town's population? Finish the division and round to the nearest percent.
Answer:
≈ 14%
Step-by-step explanation:
percent increase is calculated as
[tex]\frac{increase}{original}[/tex] × 100%
Increase = 16489 - 14523 = 1966 , then
percent increase = [tex]\frac{1966}{14523}[/tex] × 100% = [tex]\frac{1966(100)}{14523}[/tex] ≈ 14% ( to nearest percent )
Answer:
14% :)
Step-by-step explanation:
the value of x-y+xy if x=1 y=1 is
Answer:
1
Step-by-step explanation:
x-y+xy=1-1+1*1=0+1=1
Answer:
1
Step-by-step explanation:
X=1
Y=1
here,
x-y+xy=1-1+1×1
or,x-y+xy=0+1=1
Staysafe❤
if f(x) = 3x - 12 what is f(2)
Answer:
-6
(3*2)-12
6-12
-6
Step-by-step explanation:
Answer:
[tex]f(2) = -6[/tex]
Step-by-step explanation:
[tex]f(x) = 3x - 12[/tex]
[tex]f(2) = 3(2) - 12[/tex]
[tex]f(2) = 6 - 12[/tex]
[tex]f(2) = -6[/tex]
Hope it is helpful....Find the standard form for the equation of the line which passes through the point (10, 53) and which has a y-intercept of — 3.
Answer:
Step-by-step explanation:
eq. of line with slope m and intercept 3 is
y=mx+3
∵ it passes through (10,53)
53=10m+3
10m=53-3=50
m=50/10=5
y=5x+3
so standard form of eq. is
5x-y+3=0
or
5x-y=-3
Look at pic for question and answer choices.
Al sumar y/o restar números decimales, siempre se debe aplicar la norma de los signos. * 1 punto FALSO VERDADERO
Answer:
La norma de los signos es para el producto de números reales, y la norma es la siguiente.
(+)*(+) = (+)
(+)*(-) = (-)
(-)*(+) = (-)
(-)*(-) = (+)
Es decir, el producto de dos números de mismo signo es siempre positivo
El producto de dos números de distinto signo es siempre negativo.
Particularmente, para la suma esta norma no funciona (pues no está definida para la suma)
Pero en casos como:
5 - (-4)
(esto sería: "la diferencia entre cinco y menos cuatro")
notar que podemos reescribir esto como:
5 + (-1)*(-4)
Ahora podemos aplicar la norma de los signos:
5 + 4 = 9
Donde aplicamos la norma de los signos,
Podemos concluir que, si bien es una regla que aplica al producto, siempre la tenemos que tener en cuenta en cualquier operación que hagamos.
Por lo podemos concluir que la respuesta correcta es verdadero.
Find the TWO integers whos product is -12 and whose sum is 1
Answer:
[tex] \rm Numbers = 4 \ and \ -3.[/tex]
Step-by-step explanation:
Given :-
The sum of two numbers is 1 .
The product of the nos . is 12 .
And we need to find out the numbers. So let us take ,
First number be x
Second number be 1-x .
According to first condition :-
[tex]\rm\implies 1st \ number * 2nd \ number= -12\\\\\rm\implies x(1-x)=-12\\\\\rm\implies x - x^2=-12\\\\\rm\implies x^2-x-12=0\\\\\rm\implies x^2-4x+3x-12=0\\\\\rm\implies x(x-4)+3(x-4)=0\\\\\rm\implies (x-4)(x+3)=0\\\\\rm\implies\boxed{\red{\rm x = 4 , -3 }}[/tex]
Hence the numbers are 4 and -3
Answer:
Step-by-step explanation:
If the product of 2 integers is -12, then that equation looks like this:
xy = -12
If the sum of those same 2 integers in 1, then that equation looks like this:
x + y = 1
Let's solve the second equation for x and plug it into the first equation. Solving the second equation for x gives us
x = 1 - y and plug that into the first equation in place of x to get:
(1 - y)y = -12 and
[tex]y-y^2=-12[/tex] Now move everything over to one side and factor to find y:
[tex]-y^2+y+12=0[/tex] and the 2 values for y are
y = -3 and y = 4. Let's see what happens when we solve for x.
If xy = -12 and y is -3:
x(-3) = -12 so
x = 4
If xy = -12 and y is4:
x(4) = -12 so
x = -3
So it looks like the 2 integers are -3 and 4
99 boys and 1 girl are in a lecture theatre. how many boys must leave the theatre so that the percentage of boys becomes 98%?
99 boys and 1 girl makes 99 percent of boys. To make it 98%, 50 boys must leave the theatre, so there are 49 boys and 1 girl, making 98% of boys.
explain correct answer pls!!
If t = 20u and r= 5u/2 , which of the following is equivalent to 3rt, in terms of u?
A) 50u^2
B) 150u^2
C) 200u^2
D) 300u^2
Answer:
B
Step-by-step explanation:
t = 20u
r = 5u/2
3rt = 3((20u)(2.5u))
3rt = 3(50u)
3rt = 150u
The value for the expression 3rt is 50u².
What is Equation?Equations are mathematical statements with two algebraic expressions flanking the equals (=) sign on either side.
It demonstrates the equality of the relationship between the expressions printed on the left and right sides. LHS = RHS is a common mathematical formula.
Coefficients, variables, operators, constants, terms, expressions, and the equal to sign are some of the components of an equation. The "=" sign and terms on both sides must always be present when writing an equation.
Given:
We have t = 20u and r= 5u/2.
We have to find the value of 3rt by putting the value of t and r as
3rt
= 3 (5u/ 2) (20u)
= 5u x 10u
= 50 u x u
= 50 u²
Learn more about Equation here:
https://brainly.com/question/29657992
#SPJ2
Find ∠MPN
Help me please
Answer:
[tex]22^{\circ}[/tex]
Step-by-step explanation:
Line [tex]\overline{PM}[/tex] is a diameter of the circle because it passes through the circle's center O. Therefore, arc [tex]\widehat{PLM}[/tex] must be 180 degrees, as these are 360 degree in a circle.
We can then find the measure of arc [tex]\widehat{LM}[/tex]:
[tex]\widehat{LP}+\widehat{LM}=180^{\circ},\\92^{\circ}+\widehat{LM}=180^{\circ},\\\widehat{LM}=88^{\circ}[/tex]
Arc [tex]\widehat{LM}[/tex] is formed by angle [tex]\angle LPM[/tex]. Define an inscribed angle by an angle with a point on the circle creating an arc on the circumference of the circle. The measure of an inscribed angle is exactly half of the measure of the arc it forms.
Therefore, the measure of [tex]\angle LPM[/tex] must be:
[tex]m\angle LPM=\frac{88}{2}=44^{\circ}[/tex]
Similarly, the measure of [tex]\angle LNP[/tex] must be:
[tex]m\angle LNP=\frac{92}{2}=46^{\circ}[/tex]
Angles [tex]\angle LPM[/tex] and [tex]\angle MPN[/tex] form angle [tex]\angle LPN[/tex], which is one of the three angles in [tex]\triangle LPN[/tex]. Since the sum of the interior angles of a triangle add up to 180 degrees, we have:
[tex](\angle MPN+\angle LPM)+\angl+ PLN+\angle LNP=180^{\circ},\\\angle MPN+44+46+68=180,\\\angle MPN=180-44-46-68,\\\angle MPN=\boxed{22^{\circ}}[/tex]