Answer: The amount of salt in the tank after 8 minutes is 36.52 pounds.
Step-by-step explanation:
Salt in the tank is modelled by the Principle of Mass Conservation, which states:
(Salt mass rate per unit time to the tank) - (Salt mass per unit time from the tank) = (Salt accumulation rate of the tank)
Flow is measured as the product of salt concentration and flow. A well stirred mixture means that salt concentrations within tank and in the output mass flow are the same. Inflow salt concentration remains constant. Hence:

By expanding the previous equation:

The tank capacity and capacity rate of change given in gallons and gallons per minute are, respectivelly:

Since there is no accumulation within the tank, expression is simplified to this:

By rearranging the expression, it is noticed the presence of a First-Order Non-Homogeneous Linear Ordinary Differential Equation:
, where
.

The solution of this equation is:

The salt concentration after 8 minutes is:

The instantaneous amount of salt in the tank is:
I think its a
because the line segments connect each other.
After having done this on paper:

We want to isolate the variable, and the first step is to subtract the 8.

Since the <em>n</em> is being multiplied by 3, and that = 8, we can multiply both sides by 3.
<em>n</em> = 24
Let me know if this helped you understand better.
Also, you can check this by substituting in 24 for <em>n</em>.
1 2/3 = 5/3
4 2/5 = 22/5
5/3•22/5= 110/15
= 22/3
In the given problem there are several known and important facts to take note of. Firstly the restaurant bill without tax and tips is $28.35. Then the tax of 6.25% needs to be added with the bill. Also a tip of 20% on the original bill needs to be added to find the total cost.
Then tax on the restaurant bill = (6.25/100) * 28.35
= 1.77
So the tax on the restaurant bill is $1.77
Amount of tips given = 28.35 * (20/100)
= 5.67
Amount of tips paid is $5.67
Total cost paid in the restaurant = ( 28.35 + 1.77 + 5.67) dollars
= 35.79 dollars