James invested some money at 7% Interest. James also invested $97 more than 2 times that amount at 5%. How much is invested at each rate if James receives $315.61 in interest after one year?

An animal shelter has 21 puppies. if the puppies are 28% of the total dogs and cat population how many dogs and cats are in the animal shelter

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).

The first-serve percentage of a tennis player in a match is normally distributed with a standard deviation of 4.3%. if a sample of 15 random matches of the player is taken, the mean first-serve percentage is found to be 26.4%. what is the margin of error of the sample mean? a. 0.086% b. 0.533% c. 1.11% d. 2.22%