If scores on an exam follow an approximately normal distribution with a mean of 76.4 and a standard deviation of 6.1 points, then the minimum score you would need to be in the top 2% is equal to 88.929.
A problem of this type in mathematics can be characterized as a normal distribution problem. We can use the z-score to solve it by using the formula;
Z = x - μ / σ
In this formula the standard score is represented by Z, the observed value is represented by x, the mean is represented by μ, and the standard deviation is represented by σ.
The p-value can be used to determine the z-score with the help of a standard table.
As we have to find the minimum score to be in the top 2%, p-value = 0.02
The z-score that is found to correspond with this p-value of 0.02 in the standard table is 2.054
Therefore,
2.054 = x - 76.4 ÷ 6.1
2.054 × 6.1 = x - 76.4
12.529 = x - 76.4
12.529 + 76.4 = x
x = 88.929
Hence 88.929 is calculated to be the lowest score required to be in the top 2%.
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Answer:
C: X <= 7
Step-by-step explanation:
Reimagine the inequality as
3 - 1 >= X - 5/7*X
2 >= 2/7*X
1 >= 1/7 * X
7 >= X
He donated $285 to the salvation army.
The first thing to do is solve for "x". The equation would be {2(3x+60)}+5x+100=550.
Then, you would multiply 2 with 3x and 60. Your new equation would be 5x+120+5x+100=550.
Next, you would combine like terms. This means to combine the terms that are similar. In this case, it would be the whole numbers and the numbers with the variable. Your new equation would be 10x+220=550.
After that, you subtract 220 on both sides of the equal sign. This makes the equation 10x=330.
Then, you divide ten on both sides of the equal sign, giving you x=33.
The second things to is replace the x with 33. The amount for the salvation army is 5x+120. Replacing 33 with x, your final equation will be 165+120=$285.
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Answer:
13.75
Step-by-step explanation:
make a ratio between the original lengths, 11 : 5.5
then put the ratio of the enlarged lengths, 27.5 : __
now you divide 27.5 by 11 to find how many times you multiplied the lengths, 2.5.
now you multiply 5.5 by 2.5 giving you the answer of 13.75
Given:
Total number of students = 27
Students who play basketball = 7
Student who play baseball = 18
Students who play neither sports = 7
To find:
The probability the student chosen at randomly from the class plays both basketball and base ball.
Solution:
Let the following events,
A : Student plays basketball
B : Student plays baseball
U : Union set or all students.
Then according to given information,




We know that,



Now,





It means, the number of students who play both sports is 5.
The probability the student chosen at randomly from the class plays both basketball and base ball is


Therefore, the required probability is
.