An ice cream shoppe charges $1.19 for a scoop of ice cream and $0.49 for each topping. Jeb paid $4.55 for a three scoop sundae.
1 answer:
You might be interested in
Answer:
(a)
(b)
Step-by-step explanation:
Let X and Y be discrete random variables and E(X) and Var(X) are the Expected Values and Variance of X respectively.
(a)We want to show that E[X + Y ] = E[X] + E[Y ].
When we have two random variables instead of one, we consider their joint distribution function.
For a function f(X,Y) of discrete variables X and Y, we can define
Since f(X,Y)=X+Y
Let us look at the first of these sums.
Similarly,
Combining these two gives the formula:
Therefore:
(b)We want to show that if X and Y are independent random variables, then:
By definition of Variance, we have that:
Since X and Y are independent, Cov(X,Y)=0
Therefore as required:
Step-by-step explanation:
1)
In a right triangle longest side is hypotenuse and the remaining two sides represent the perpendicular legs.
Hence, from the given question it is obvious that 25 is hypotenuse and 20 and 15 are perpendicular legs.
Now, by Pythagorean theorem:
2)
Because all right triangles have one hypotenuse and two perpendicular legs.