Answer:
Step-by-step explanation:
This is a differential equation problem most easily solved with an exponential decay equation of the form
. We know that the initial amount of salt in the tank is 28 pounds, so
C = 28. Now we just need to find k.
The concentration of salt changes as the pure water flows in and the salt water flows out. So the change in concentration, where y is the concentration of salt in the tank, is 
. Thus, the change in the concentration of salt is found in
inflow of salt - outflow of salt
Pure water, what is flowing into the tank, has no salt in it at all; and since we don't know how much salt is leaving (our unknown, basically), the outflow at 3 gal/min is 3 times the amount of salt leaving out of the 400 gallons of salt water at time t:
Therefore,
or just
and in terms of time,
Thus, our equation is
and filling in 16 for the number of minutes in t:
y = 24.834 pounds of salt
Answer:
95% Confidence interval: (96.06,103.94)
Step-by-step explanation:
We are given the following in the question:
Population mean, μ = 85
Sample mean, 
= 100
Sample size, n = 30
Alpha, α = 0.05
Population standard deviation, σ = 11
95% Confidence interval:
Putting the values, we get,
(96.06,103.94) is the 95% confidence interval for the population mean test score.
Answer:
( 2 - x )^2
Step-by-step explanation:
Answer:
32 rooms
Step-by-step explanation:
You have to divide
The volume for any cube is length x width x height,
so in this case because all side of cube is the same, let it be y.
y x y x y = 27
y = 3
so each side will be 3 inches
