Dave Bowers collects U. S. gold coins. He has a collection of 49 coins. Some are​ $10 coins, and the rest are​ $20 coins. If the face value of the coins is ​$690​, how many of each denomination does he​ have? How many $10 coins does he have?
How many $20 coins does he have?

Determine the mean and variance of the random variable with the following probability mass function. f(x)=( 729divided by 91) (1 divided by 9) superscript x baseline comma x equals 1,2,3 round your answers to three decimal places (e. g. 98.765).

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?

Write the point-slope form of the line passing through (2, -12) and parallel to y=3x.