Question

Two catalysts in a batch chemical process, are being compared for their effect on the output of the process reaction. A sample of 12 batches was prepared using catalyst 1, and a sample of 10 batches was prepared using catalyst 2. The 12 batches for which catalyst 1 was used in the reaction gave an average yield of 85 with a sample standard deviation of 4, and the 10 batches for which catalyst 2 was used gave an average yield of 81 and a sample standard deviation of 5. Find a 90% confidence interval for the difference between the population means, assuming that the populations are approximately normally distributed with equal variances.

Answer 1

Answer:

2.083 < µ1 - µ2 < 5.917  

Step-by-step explanation:

We will need to construct a 90% confidence interval for the difference of 2 means where the populations are normally distributed, and their variances are equal.

The calculations of the sample means and standard deviations are done for us.

Sample 1: Catalyst 1

n = 12, x = 85, s = 4

Sample 2:  Catalyst 2

n = 10, x = 81, s = 5

See attached photo for the construction of the confidence interval...