Answer and Explanation:
Given : The random variable x has the following probability distribution.
To find :
a. Is this probability distribution valid? Explain and list the requirements for a valid probability distribution.
b. Calculate the expected value of x.
c. Calculate the variance of x.
d. Calculate the standard deviation of x.
Solution :
First we create the table as per requirements,
x P(x) xP(x) x² x²P(x)
0 0.25 0 0 0
1 0.20 0.20 1 0.20
2 0.15 0.3 4 0.6
3 0.30 0.9 9 2.7
4 0.10 0.4 16 1.6
∑P(x)=1 ∑xP(x)=1.8 ∑x²P(x)=5.1
a) To determine that table shows a probability distribution we add up all five probabilities if the sum is 1 then it is a valid distribution.


Yes it is a probability distribution.
b) The expected value of x is defined as

c) The variance of x is defined as

d) The standard deviation of x is defined as



Answer:
<h3>6 degrees</h3>
Step-by-step explanation
Find the diagram attached. In Line geometry, there is a theorem that states that the sum of the adjacent interior angles is 180 degrees. According to the diagram, the adjacent interior angles are 7x- 15 and 24x + 9.
The sum of this angles must give 180 degrees as shown;
7x-15 + 24x + 9 = 180
7x+24x-15+9 = 180
31x-6 = 180
31x = 180+6
31x = 186
x = 186/31
x = 6
Hence the value of x is 6 degrees
Answer:
19y+5
Step-by-step explanation:
Combine like terms look for all the numbers that have y attached and combine them
7y +12y=19y
Look for terms where nothing is attached it's just the number combine them
6-1=5
Put all together again and you get:
19y+5
Given:
a square with an area of a² is enlarged to a square with an area of 25a².
The side length of the smaller square was changed when The side length was multiplied by 5.
Area = (1a)² = a²
Area = 1a * 5 = 5a ⇒ (5a)² = 25a²