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

answer: it's a

step-by-step explanation:

answer: the price of one pound cabbage = $ 0.8

the point (10,8) represents that the cost of 10 pounds cabbage is $ 8

step-by-step explanation:

since, here is a proportional relation between the number of pounds of cabbage (x) and the price in dollars (y).

therefore, we can write,

⇒ y = k x

where k is the constant of proportionality.

now, point (5,4) is in the line.

thus, it will satisfies the above equation of line.

⇒ 4 = 5 k

⇒ k = 0.8

thus, the equation of the line is,

y = 0.8 x

a) for x = 1,

y = 0.8

therefore, the cost of one pound of cabbage is 0.8 dollars.

b) in the below graph (10,8) represents that the cost of 10 pounds of cabbage is 8 dollars.