Answer:
Step-by-step explanation:
Given that a large mixing tank initially holds 400 gallons of water in which 70 pounds of salt have been dissolved. Pure water is pumped into the tank at a rate of 4 gal/min, and when the solution is well stirred, it is then pumped out at the same rate.
Let Q(t) be the quantity of salt at time t.
Q(0) = 70 pounds
Inflow of water = outflow = 4 gal/min
So resulting volume of tank at time t = 400 gallons
Rate of change of salt = inflow - outflow
= 0 - 
i.e. 
This is a variable separable equation
Use when t =0 Q = 70
A =70
So A(t) = Q(t) = 
and
A(0) = Q(0) = 70 lbs.
Answer: I think the answer is B
Step-By-Step Explination:
First you find out what x is by doing 42 multiplying it by 0.1 witch equals 4.2 gallons per mile
Next you figure out what y is by doing 4.2y (witch is 4.2 times y)
Answer:
The number is 91
Step-by-step explanation:
Let x be the ones place digit and y be the tens place digit,
Then the number would be 10y + x,
We have,
y - x = 8
Possible values of y and x = { (8, 0), (9, 1) }
∵ 0 is not the digit of the number,
Hence, y = 9 and x = 1
Therefore, required number = 10(9) + 1 = 90 + 1 = 91
Answer:
Step-by-step explanation:
<u><em>Using Pythagorean Theorem:</em></u>
=> 
Where c is hypotenuse, a is base and b is perpendicular and ( a, b = 4)
=> 
=> 
=> 
Taking sqrt on both sides
=> c = 5.7 units
Answer: The numbers are 1 and 2
Step-by-step explanation:
