Parallelogram area = base * height
240 = base * 20
base = 240 / 20
base = 12 cm
you got all right just check it and do the other one
Answer:
a)
And replacing we got:
b)
Step-by-step explanation:
Previous concepts
In statistics and probability analysis, the expected value "is calculated by multiplying each of the possible outcomes by the likelihood each outcome will occur and then summing all of those values".
The variance of a random variable Var(X) is the expected value of the squared deviation from the mean of X, E(X).
And the standard deviation of a random variable X is just the square root of the variance.
Solution to the problem
Part a
We have the following distribution function:
Y 0 1 2 3
P(Y) 0.45 0.2 0.3 0.05
And we can calculate the expected value with the following formula:
And replacing we got:
Part b
For this case the new expected value would be given by:
And replacing we got
Answer: - x - 120
Explanation: You want to find the opposite of (120-x) not just x, so you just put the negative symbol next to both the variables.