Ms. Gonzalez buys folders for her office. She buys 4 small folders for every 1 large folder. She buys 15 folders in all. Small folders cost $0.75, and large folders cost
$1.25. How much more money does Ms. Gonzalez spend on small folders than
large folders? Show your work.

Researchers were interested in whether relaxation training decreases the number of headaches a person experiences. they randomly assigned 20 participants to a control group or a relaxation training group and noted the change in number of headaches each group reported from the week before training to the week after training. which statistical analysis should be performed to answer the researchers' question?