I did say the answer is $35. Because, you should use the highest factor or whatever operation the problem is using, to find the answer. Not sure if it's some two-step problem....
As we already have the model that describes the change of the population in Italy in terms of the years that have elapsed, we only have to replace the conditions that are requested in that equation.
Therefore to find the population of Italy in the year 2000 (t = 10 years) substitute t = 10 in the equation and have:
million people
To find the population of Italy in 2008 (t = 18 years)
substitute t = 18 in the equation and have:
million people
To predict the population in Italy for 2015 and 2020 with this model, we substitute in the equation t = 25 and t = 30
t = 25
million people
t = 30
million people
Answer:
As the calculated value of z does not lie in the critical region the null hypothesis is accepted that the GPA mean of the night students is the same as the GPA mean of the day students.
Step-by-step explanation:
Here n= 20
Sample mean GPA = x`= 2.84
Standard mean GPA = u= 2.55
Standard deviation = s= 0.45.
Level of Significance.= ∝ = 0.01
The hypothesis are formulated as
H0: u1=u2 i.e the GPA of night students is same as the mean GPA of day students
against the claim
Ha: u1≠u2
i.e the GPA of night students is different from the mea GPA of day students
For two tailed test the critical value is z ≥ z∝/2= ± 2.58
The test statistic
Z= x`-u/s/√n
z= 2.84-2.55/0.45/√20
z= 0.1441
As the calculated value of z does not lie in the critical region the null hypothesis is accepted that the GPA mean of the night students is the same as the GPA mean of the day students.
Multiply the first equation by -2. It turns into 4x+18y=50 and the other one stays -4x-9y=-23. Then you "eliminate" the equations by "adding" them. Set it up like this:
4x+18y=50
+
-4x-9y=-23
4x-4x= 0. 18y-9y= 9y and 50-23= 27
SO: 9y= 27 and y= 3
And then you plug that in to one equation: 4x +18(3)= 50. 4x= 50-(18*3)
4x= -4, so x=-1.
Plug it back in to check!
Hope this helps. Happy solving! :)
Answer: 210
<em>Step-by-step explanation: 70+70+70=210 and 40% for 210 students would add up to 120% of all students surveyed. Look if there is 70 students that's been surveyed that is 40% add 40% 3 times(40%+40%+40%)=120% of all students surveyed </em>
