Brigitte cleans out the loose change from the cup holder in her car (pennies, nickels, and dimes). she finds three more nickels than dimes, and six more pennies than twice the number of nickels. if the total value of the coins is $2.31, how many of each coin did she have in her cup holder? it needs to be solved using linear equations of three variables and i don't understand how to do that.

If private savings 'v' = 0.75s and total savings 's' equals $4.20 billion, solve for public and private savings.

3.17 scores on stats final. below are final exam scores of 20 introductory statistics students. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 57, 66, 69, 71, 72, 73, 74, 77, 78, 78, 79, 79, 81, 81, 82, 83, 83, 88, 89, 94 (a) the mean score is 77.7 points. with a standard deviation of 8.44 points. use this information to determine if the scores approximately follow the 68-95-99.7% rule. (b) do these data appear to follow a normal distribution? explain your reasoning using the graphs provided below.

What are the solutions of the equation x4 + 6x2 + 5 = 0? use u substitution to solve.