Ateacher is experimenting with a new computer-based instruction and conducts a study to test its effectiveness. in which situation could the teacher use the two-sample t-test for comparing two population means?

From a normally distributed population,  if two samples of size less than 30 taken out , then we use t-test to test the difference between the population means.

The conditions which are necessary to use a t-test are :-

1. Each population must have normal distribution.

2. Both the samples must be independent.

Now, if a teacher is experimenting with a new computer-based instruction and conducts a study to test its effectiveness, then to use a t-test all the above conditions are necessary.

x=45

Step-by-step explanation:

x+x+1+x+2=138

3x+3=138

3x=138-3

3x=135