Answer:
Step-by-step explanation:
Volume of tank is 3000L.
Mass of salt is 15kg
Input rate of water is 30L/min
dV/dt=30L/min
Let y(t) be the amount of salt at any time
Then,
dy/dt = input rate - output rate.
The input rate is zero since only water is added and not salt solution
Now, output rate.
Concentrate on of the salt in the tank at any time (t) is given as
Since it holds initially holds 3000L of brine then the mass to volume rate is y(t)/3000
dy/dt= dV/dt × dM/dV
dy/dt=30×y/3000
dy/dt=y/100
Applying variable separation to solve the ODE
1/y dy=0.01dt
Integrate both side
∫ 1/y dy = ∫ 0.01dt
In(y)= 0.01t + A, .A is constant
Take exponential of both side
y=exp(0.01t+A)
y=exp(0.01t)exp(A)
exp(A) is another constant let say C
y(t)=Cexp(0.01t)
The initial condition given
At t=0 y=15kg
15=Cexp(0)
Therefore, C=15
Then, the solution becomes
y(t) = 15exp(0.01t)
At any time that is the mass.
Answer:
D
Step-by-step explanation:
given the 2 equations
x + 2y = 27 → (1)
2x + 3y = 46 → (2)
Rearrange (1) expressing x in terms of y by subtracting 2y from both sides
x = 27 - 2y ← substitute into (2)
2(27 - 2y) + 3y = 46
54 - 4y + 3y = 46
54 - y = 46 ( subtract 54 from both sides )
- y = - 8 ( multiply both sides by - 1 )
y = 8 → D
Answer:
d = 2cot(x) or d = 2/tan(x)
Step-by-step explanation:
The vertical distance from the jet to the top of the house represents the opposite side to the 'x' angle, while the horizontal distance, d, represents the adjacent side. Since we do not know the hypotenuse, the tangent and cotangent functions are the preferable choices:

Therefore, the distance 'd' can be expressed as d = 2cot(x) or d = 2/tan(x).
Answer:
2x -6
Step-by-step explanation:
2x is slope
-6 is y intercept
The function passes though -6
a slope of 2 means the function goes up 2 and over 1 unit for every 1 x unit
Answer:
Step-by-step explanation:
<u>The balls - multiples of 3 are:</u>
<u>The probability of a multiple of 3 is:</u>
- 3 out of 10 or
- P = 3/10 = 30%
30% probability is in the range 0%-50% so this event is unlikely