A company's profit can be modeled by the equation p(u)=-u^2+180u+1000 where 'u' is the number of units sold. Find the maximum profit of the company. How many units should the company sell to maximize profit? (Hint: set your window to xmin=-20 xmax=200 to see the sides of the parabola then adjust your ymax to see the vertex of the parabola.)

How to solve a simultaneous equation involved with fractions?

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.

Carl's candies has determined that a candy bar measuring 3 inches long has a z-score of +1 and a candy bar measuring 3.75 inches long has a z-score of +2. what is the standard deviation of the length of candy bars produced at carl's candies?