Answer: (15.47, 24.53)
Step-by-step explanation:
We know that the confidence interval for population mean is given by :_
, where n= sample size.
= standard deviation.
= sample mean.
z*= Critical value.
Given : n= 450
Critical value for 95% confidence = z*=1.96 [From z-value table]
Then, the 95% confidence interval will be :-
Hence, the 95% confidence interval for the mean change in score μ μ in the population of all high school seniors. : (15.47, 24.53)
We can set up a system of equations to solve this.
120b + 90d = 270
60b + 110d = 265
To cancel out b, first make the b terms equal.
60b · 2 + 110d · 2 = 265 · 2
120b + 220d = 530
Now subtract the equations.
120b + 90d = 270
-120b + 220d = 530
---------------------------
-130d = -260
Solve for d.
-130d/-130 = -260/-130
d = 2
Now put the value of d in one of the equations.
60b + 110d = 265
60b + 110 · 2 = 265
60b + 220 = 265
60b + 220 - 220 = 265 - 220
60b = 45
60b/60 = 45/60
b = 0.75
Each candy bar sells for $0.75
Hope this helps! :)
The answer issssssssssssss 72.42
-4,5. 4,5 that would be the answer it's like the oppiste
Do you have a picture for this problem? There are multiple different ways to solve this problem but I'll need a picture to help you.
