Agovernment agency has specialists who analyze the frequencies of letters of the alphabet in an attempt to decipher intercepted messages. in standard english text, a particular letter is used at a rate of 6.8%.
a. find the mean and standard deviation for the number of times this letter will be found on a typical page of 3000 characters.

If f(x)=2x-6 and g(x)=3x+9, find (f-g)(x)

Adj has a total of 1075 dance and rock songs on her system. the dance selection is 4 times the size of the rock selection. write a system of equations to represent the situation.

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.