Question

Example 4
In an experiment to study the effect of the spectrum of the ambient light on the growth of plants, researchers assigned tobacco seedlings at random to two groups of eight plants each. The plants were grown in a greenhouse under identical conditions except for lighting. The experimental group was under blue light, the control group under natural light. Here are the data on stem growth in millimeters:

Control Group Experimental
4.3 4.2 3.9 4.1 3.1 2.9 3.2 3.2 4.1 4.2 3.8 4.1 2.7 2.9 3.0 3.1

Construct a 90% confidence interval for the difference in population means.

       

Answer 1