Answer:
0.4
Step-by-step explanation:
you just have to divide
2÷5=0.4
Ed has $37 and decides that he wants to go out to lunch with his friend Barb. They go out to eat, and when it comes time to pay the bill they decide to split it. It will cost Ed $12 to pay his half. How much money will he have left after he pays his share?
For which question, I can help,
<span>for number 9, parallel lines have the same exact slope, so divide each of them by to isolate the y and then see if the slope (number multiplied by x) is the same as the other problems . PS: focus on the slope, rest of equation doesn't matter in this question</span>
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.
So get b alone.
A=bh
Divide by h
A/h=b
b is alone
And just to rearrange:
b=A/h
