Set up and solve a system of equations to solve the problem. A jar contains n nickels and d dimes. There are 18 coins in the jar, and the total value of the coins is $1.30. How many nickels and how many dimes are in the jar?

The jar contains
nickels and
dimes.

The lengths of nails produced in a factory are normally distributed with a mean of 4.91 centimeters and a standard deviation of 0.05 centimeters. find the two lengths that separate the top 4% and the bottom 4%. these lengths could serve as limits used to identify which nails should be rejected. round your answer to the nearest hundredth, if necessary.

What are “like terms”? why can we only add like terms?

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?