10n - 20p + 20
could i get a heart and branliest
12 because the rest of the numbers are all similar except 12
Answer:
Step-by-step explanation:
H0 : μ = 46300
H1 : μ > 46300
α = 0.05
df = n - 1 = 45 - 1 = 44
Critical value for a one tailed t-test(since population standard deviation is not given).
Tcritical = 1.30
The test statistic :(xbar - μ) ÷ (s/sqrt(n))
The test statistic, t= (47800-46300) ÷ (5600√45)
t = 1500
t = 1500 / 834.79871
t = 1.797
The decision region :
Reject H0: if t value > critical value
1. 797 > 1.30
Tvalue > critical value ; We reject H0
Hence, there is sufficient evidence to conclude that cost has increased.
Cramer's rule works as follows:
x+3y=16
3x+y=8
Then
x=Dx/D
y=Dy/D
where Dx,Dy,D are 2x2 matrices formed from of coefficients and right hand side.
D=
1 3
3 1
=1-9=-8
Dx=matrix D with first column replaced by the vector [16,8]=
16,3
8 1
=16-24
=-8
Dy=matrix D with second column replaced by the vector [16,8]=
1 16
3 8
=8-48
=-40
Therefore
x=-8/-8=1
y=--40/-8=5
Check:
x+3y=1+3(5)=16
3x+y=3(1)+5=8 ok.
By using the rule -b/2a —> 12/-6= -2
