Answer
a) y | p(y)
25 | 0.8
100 | 0.15
300 | 0.05
E(y) = ∑ y . p(y)
E(y) = 25 × 0.8 + 100 × 0.15 + 300 × 0.05
E(y) = 50
average class size equal to E(y) = 50
b) y | p(y)
25 | 
100 | 
300 | 
E(y) = ∑ y . p(y)
E(y) = 25 × 0.4 + 100 × 0.3 + 300 × 0.3
E(y) = 130
average class size equal to E(y) = 130
c) Average Student in the class in a school = 50
Average student at the school has student = 130
The value of x from the given expression is; x= -2/3
<h3>Solving one-variable equations</h3>
The given expression is;
Hence, when we expand the equation; we have;
Read more on one-variable equations;
brainly.com/question/21528555
Answer:
So I assume we are figuring out the number of men and women here, so:
m + 2w = 12
m = 12 - 2w
12 - 2w + 3w = 22
w = 10
m + 2w = 12
m + 2(10) = 12
m + 20 = 12
m = -8
Multiply 2/10 by 3/1 and you should end up with 6/10
X + y = 4...x = 4 - y
2x + 3y = 0
2(4-y) + 3y = 0
8 - 2y + 3y = 0
-2y + 3y = 0 - 8
y = -8
x + y = 4
x - 8 = 4
x = 4 + 8
x = 12
solution is : (12,-8)