Grades can be converted into numbers ( as in calculating a gpa where an a=4, b=3,c=2, d=1, and f=0
x grade 4 3 2 1 0
p(x) 0.20 0.25 0.30 0.10 0.15

a. verify that this is a legitimate probability distribution 0.20+0.25+0.30+0.10+0.15=1
b. find the means grade for this class.
4x0.20=0.8
3x0.25=0.75
2x0.30=0.6
1x0.10=0.1
0x0.15=0.0

0.8+0.75+0.6+0.1+0.0=2.25
find the standard deviation
c. 2.25/5=0.45

George is folding a piece of paper to make an origami figure. each time he folds the paper, the thickness of the paper is doubled. the paper starts out flat, with a thickness of 1 millimeter. a. write a list of six ordered pairs showing the output as the thickness of the paper when the input is the number of times it is folded. explain how you came up with your ordered pairs. b. is this relation a function? explain why or why not using the ordered pairs you came up with in part a.

The weights of players in a basketball league are distributed normally. the distance (d) of each player's weight (w) from the mean of 86 kilograms was computed as follows: d = |w - 86| if d is greater than 7 for approximately 5% of the players, what is the approximate standard deviation of the players' weights? a. 1.75 kilograms b. 3.5 kilograms c. 4.3 kilograms d. 7 kilograms

Jose predicted that he would sell 48 umbrellas. he actually sold 72 umbrellas. what are the values of a and b in the table below? round to the nearest tenth if necessary