Answer:
We have strong evidence that on average, students study less than 150 minutes per night during the school week
Step-by-step explanation:
Normal distribution:
mean μ₀ = 150
Sample:
Sample size n = 272
Sample mean x = 141
Sample standard deviation s = 66
The standard error of the sample mean SE = σ /√n
SE = 66/√272
SE = 66 / 16,49
SE = 4
Test Hypothesis:
Null hypothesis H₀ x = μ₀
Alternative hypothesis Hₐ x < μ₀
z(s) test statistics is:
z(s) = ( x - μ₀ ) / s/√n
z(s) = - 9 /4
z(s) = - 2,25
p-value for that z(s) p-value = 0,0122
Then for α = 0,05 p-value < 0,05
We are in the rejection region we need to reject H₀
Answer:
The solutions are the following:
- z=2(cos(π6)+isin(π6))=√3+12i
- z=2(cos(2π3)+isin(2π3))=−1+i√3
- z=2(cos(7π6)+isin(7π6))=−√3−12i
- z=2(cos(5π3)+isin(5π3))=1−i√3
<em>hope this helps!! :) --Siveth</em>
Answer:
C
Step-by-step explanation:
ok so they want you to put everything but y on one side
to get rid of the -4, you add 4 to both sides
you are then left with
2/3y=x+4
multiple both sdies by 3/2
y= 3(x+4)/2
divide everything by 2
y=3/2x+6
C
