Answer:
We conclude that the mean nicotine content is less than 31.7 milligrams for this brand of cigarette.
Step-by-step explanation:
We are given the following in the question:
Population mean, μ = 31.7 milligrams
Sample mean,
= 28.5 milligrams
Sample size, n = 9
Alpha, α = 0.05
Sample standard deviation, s = 2.8 milligrams
First, we design the null and the alternate hypothesis

We use One-tailed t test to perform this hypothesis.
Formula:

Putting all the values, we have

Now,
Since,
We fail to accept the null hypothesis and accept the alternate hypothesis. We conclude that the mean nicotine content is less than 31.7 milligrams for this brand of cigarette.
Answer:
i)W = 2500 / T
ii) W = 500 Tons
iii) grad W(10°) = - 25î
iv) The formulation is not practical
Step-by-step explanation:
i) Write an equation describing the use of coal
As use of coal is inversely proportional to the average monthly temperature
if W is use of coal in tons/per month then
W(t) = k / T where k is a constant of proportionality and T is the average temperature in degrees. We have to determine k from given conditions
k = ?? we know that when T = 25° W = 100 tons the by subtitution
W = k/T 100 = k /25 k = 2500 Tons*degree
Then final equation is:
W = 2500 / T
ii) Find the amount of coal when T = 5 degrees
W = 2500 / 5
W = 500 Tons
iii)
The inverse proportionality implies that W will decrease as T increase.
The vector gradient of W function is:
grad W = DW(t)/dt î
grad W = - 2500/T² î
Wich agrees with the fact that W is decreasing.
And when T = 100°
grad W(10°) = - 2500/ 100 î ⇒ grad W(10°) = - 25î
iv) When T = 0 The quantity of coal tends to infinite and the previous formulation is not practical
Solving a system of equations we can see:
- Sutopa has $73.20
- Maneet has $97.60
- Kim has $115.60
<h3>
How much money each of them has?</h3>
First, let's define the variables:
- S = money that Sutopa has.
- M = money that Maneet has.
- K = money that Kim has.
We can write the system of equations:
S = (3/4)*M
M = K - $18
S + M + K = $286.40
First, we can rewrite the second equation to get:
K = M + $18
Now we can replace the first and second equations into the third one:
(3/4)*M + M + (M + $18) = $286.40
Now we can solve this for M:
M*(1 + 1 + 3/4) = $286.40 - $18
M = $268.40*(4/11) = $97.60
Now we can find the other two values:
K = M + $18 = $97.60 + $18 = $115.60
S = (3/4)*M = (3/4)*$97.60 = $73.20
If you want to learn more about systems of equations:
brainly.com/question/13729904
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