Answer:
The probability is
Step-by-step explanation:
From the question we are told that
Th The population mean
The standard deviation is
The values considered is
Given that the distribution of the amounts spent follows the normal distribution then the percent of the adults spend more than $2,550 per year on reading and entertainment is mathematically represented as
Generally
So
substituting values
From the normal distribution table the value of is
Thus
We calculate the z-score for the amount $2,550 using the given mean and standard deviation. The z-table gives us the percentage of people who spend less than this, which we subtract from 1 to find the percentage who spend more. Approximately 16.85% of adults in the 25- to 34-year age group spend more than $2,550 on reading and entertainment each year.
To compute the percentage of adults spending more than $2,550 per year, we must first find the z-score associated with this value. The z-score is a measurement of how many standard deviations a particular data point is from the mean.
The formula for calculating the z-score is: Z = (X - μ) / σ.
Where:
- X is the value we are interested in.
- μ is the mean.
- σ is the standard deviation.
Using this formula, the z-score for $2,550 is:
Z = ($2,550 - $1,999) / $574 = 0.96.
Next, we need to use a z-table or a standard normal distribution table to find out the probability that lies below the calculated z-score. Looking this up on a z-table, we get a value of 0.8315, meaning that 83.15% of the population will spend $2,550 or less per year on reading and entertainment. Since we want to know the percentage spending more than $2,550, we subtract this value from 1: 1 - 0.8315 = 0.1685.
Therefore, based on the given mean and standard deviation, about 16.85% of adults in the 25- to 34-year age group spend more than $2,550 on reading and entertainment each year.
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Answer:
D. 7017
Step-by-step explanation:
if 24 is the first term, find 7x999, or 7x1000-7 and add 24
however a better way would be to use the formula
value=a+(n-1)d
a = the first term in the sequence (24)
n = the amount of terms you need (1000)
d = the common difference between terms (7)
Answer:
The expected number of tests, E(X) = 6.00
Step-by-step explanation:
Let us denote the number of tests required by X.
In the case of 5 individuals, the possible value of x are 1, if no one has the disease, and 6, if at least one person has the disease.
To find the probability that no one has the disease, we will consider the fact that the selection is independent. Thus, only one test is necessary.
Case 1: P(X=1) = [P (not infected)]⁵
= (0.15 - 0.1)⁵
P(X=1) = 3.125*10⁻⁷
Case 2: P(X=6) = 1- P(X=1)
= 1 - (1 - 0.1)⁵
P(X=6) = (1 - 3.125*10⁻⁷) = 0.999999
P(X=6) = 1.0
We can then use the previously determined values to compute the expected number of tests.
E(X) = ∑x.P(X=x)
= (1).(3.125*10⁻⁷) + 6.(1.0)
E(X) = E(X) = 6.00
Therefore, the expected number of tests, E(X) = 6.00
The exact values of α and β as follows: α = 2π/3 and β = 7π/6. To find the exact value of the given trigonometric expressions, we need to use the Laws of Sines and Cosines.
The Law of Sines is a mathematical equation used to calculate the angles or sides of a triangle when two angles and one side are known. It states that the ratio of the sine of an angle to the length of the opposite side is constant.
The Law of Sines states that the ratio of a side to the sine of its opposite angle is equal for all sides and angles of a triangle. The Law of Cosines states that the square of a side of a triangle is equal to the sum of the squares of the other two sides minus twice the product of those sides multiplied by the cosine of the included angle.
We begin by finding the exact value of tan α. Using the Law of Sines, we can find the measure of α by solving the equation: tan α = 3/4 = sin α/cos α. This can be rearranged to find cos α = 4/3, and then we can use the inverse of cosine to find the exact value of α.
Using the Law of Cosines, we can find the exact value of β by solving the equation: -15/17 = (cos β)2 = (1 - sin2 β). This can be rearranged to find sin β = -4/5, and then we can use the inverse of sine to find the exact value of β.
Finally, using the given conditions, we can find the exact values of α and β as follows: α = 2π/3 and β = 7π/6.
For more questions related to cosines
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Answer:
11 1/2 years old
Step-by-step explanation:
Let Amanda's age be a.
Let the company's age be c.
The company is 24 years older than Amanda. This means that:
c = 24 + a ______(1)
The sum of Amanda's age and the company's age is 121 years. This means that:
c + a = 121 ________(2)
Put (1) in (2):
24 + a + a = 121
2a = 121 - 24
2a = 97
a = 97 / 2 = 48 1/2 years
She has been there for 37 years, therefore, her age when she started working there is:
48 1/2 - 37 = 11 1/2 years old
NOTE: This age doesn't seem right but I worked based on the parameters given.