Answer:
The interest rate of Jess's account was 7%
Step-by-step explanation:
A = P * (1 + rt)
A = final amount
P = initial principal balance
r = annual interest rate
t = time (in years)
Replacing with the values we know:
A = P * (1 + rt)
8,150 = 5,000 * (1 + r * 9)
8,150/5,000 = 1 + 9r
1.63 = 1 + 9r
1.63 - 1 = 9r
0.63 = 9r
r = 063/9
r = 0.07 = 7%
The interest rate of Jess's account was 7%
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:
x + y ≤ 12
Step-by-step explanation:
Inequality:
Not more than 12 means less than or equal to 12
x + y ≤ 12
Answer:
20 1/2 feet
Step-by-step explanation:
The total length is found by adding the lengths of the individual pieces. It can be easier if you use multiplication in place of repeated addition. You want ...
(2 × 5 feet) + (7 × 18 inches)
At some point in the process, you need to convert inches to feet. This is done by remembering that 12 inches = 1 foot. Dividing inches by 12 gives feet.
The above expression evaluates to
10 feet + 126 inches = 10 feet + (126/12) feet = 10 feet + 10.5 feet
= 20.5 feet
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