Answer:
-611.031 < μd < 4260.031
Explanation:
This is a matched pair design :
______Day1 Day 2 Day 3 Day 4
x1 Kill room 3175 2526 1763 1090
x2 Processing 529 141 362 224
First we obtain the difference, d ;
d = (x1 - x2)
d = 2646, 2385, 1401, 866
The mean difference, dbar = Σd/ n = 7298 / 4 = 1824.5
The standard deviation of difference,
Sd = √(Σx-dbar)²
Using calculator, Sd = 834.086
The 99% confidence interval :
Mean ± margin of error
dbar ± margin of error
Margin of Error = Tcritical * Sd/√n
Tcritical at 99%, df = n-1 ; df = 4-1 = 3
Tcritical = 5.84
Margin of Error = 5.84 * 834.086/√4 = 2435.53112
Confidence interval = 1824.5 ± 2435.53112
(-611.031 ; 4260.031)