The 99% confidence interval for the decrease in the defective rate after the reconfiguration is (-0.018, 0.086).
<h3>How to find Confidence Intervals?</h3>
Let the random variable & parameters be;
x1 : Number of successes from group 1
x2 : Number of successes from group 2
p1: Proportion of successes in group 1
p2: Proportion of successes in group 2
n1 : number of trial in group 1
n2: number of trial in group 2
We are given;
x1 = 260
n1 =985
x2 = 194
n2 = 842
Thus;
p1 = 260/985
p1 =0.2640
p2 = 194/842
p2 = 0.2304
Constructing a (1 - α)100% confidence interval for proportion from the formula;
(p₁ - p₂) - z√[((p₁(1 - p₁)/n₁) + p₂(1 - p₂)/n₂)]
plugging in z = 2.576 and the values of p₁, p₂, n₁ and n₂, we have the confidence interval as;
(-0.0184631, 0.0855743)
Therefore the 99% confidence interval for the decrease in the defective rate after the reconfiguration is (-0.018, 0.086).
Read more about Confidence Interval at; brainly.com/question/17097944
#SPJ1
