Answer:
(a) Approximately 95% of women with platelet counts within 2 standard deviations of the mean.
(b) Approximately 99.7% of women have platelet counts between 65.2 and 431.8.
Step-by-step explanation:
The complete question is: The blood platelet counts of a group of women have a bell-shaped distribution with a mean of 248.5 and a standard deviation of 61.1. (All units are 1000 cells/mul.) using the empirical rule, find each approximate percentage below.
a. What is the approximate percentage of women with platelet counts within 2 standard deviations of the mean, or between 126.3 and 370.7?
b. What is the approximate percentage of women with platelet counts between 65.2 and 431.8?
We are given that the blood platelet counts of a group of women have a bell-shaped distribution with a mean of 248.5 and a standard deviation of 61.1.
Let X = the blood platelet counts of a group of women
The z-score probability distribution for the normal distribution is given by;
Z = ~ N(0,1)
where, = population mean = 248.5
= standard deviation = 61.1
Now, the empirical rule states that;
(a) The approximate percentage of women with platelet counts within 2 standard deviations of the mean, or between 126.3 and 370.7 is given by;
As we know that;
P( < X < ) = 0.95
P(248.5 - 2(61.1) < X < 248.5 + 2(61.1)) = 0.95
P(126.3 < X < 370.7) = 0.95
Hence, approximately 95% of women with platelet counts within 2 standard deviations of the mean.
(b) The approximate percentage of women with platelet counts between 65.2 and 431.8 is given by;
Firstly, we will calculate the z-scores for both the counts;
z-score for 65.2 =
= = -3
z-score for 431.8 =
= = 3
This means that approximately 99.7% of women have platelet counts between 65.2 and 431.8.
Using the empirical rule, approximately 68% of values fall within 1 standard deviation from the mean in a bell-shaped distribution. For ranges 2 or 3 standard deviations from the mean, the respective approximate percentages are 95% and 99.7%.
The question refers to the Empirical rule, which in statistics, is also known as the Three-sigma rule or the 68-95-99.7 rule. This rule is a shortcut for remembering the proportion of values in a normal distribution that are within a given distance from the mean: 68% are within 1 standard deviation, 95% are within 2 standard deviations, and 99.7% are within 3 standard deviations.
Without given specific values for the mean or standard deviations, we can discuss the problem in a general sense:
#SPJ3
Answer: The answer is 1,024.
Explanation: 32^2 is 32 x 32, which is 1,024.
Answer: $0.25
Step-by-step explanation:
We are given that the cost of 12 goldfish = $3
To find the cost of one goldfish we use division operator and divide the cost of 12 gold fishes by 12.
Then , the cost of one gold fish =
⇒ Cost of 1 gold fish
⇒ Cost of 1 gold fish [Divide numerator and denominator by 3.]
⇒ Cost of 1 gold fish [Simplify by dividing 1 by 4]
Therefore , the cost of 1 goldfish = $0.25
Answer:
0.25
Step-by-step explanation:
Answer:
87.5
Edited: Yea should be 56, misread it LOL.
Appoligise to that silly mistake
Step-by-step explanation:
Answer:
-6
Step-by-step explanation:
Let the first, second and third number be x, y and z respectively.
We are told that the second number is subtracted from the sum of the first number and 3 times the third number, the result is 2.
Thus;
(x + 3z) - y = 2 - - - (eq 1)
The third number plus 3 times the first number is -1.
Thus;
z + 3x = -1 - - - (eq 2)
The first number plus 3 times the second number plus the third number is -16.
Thus;
x + 3y + z = -16 - - - (eq 3)
From eq 2, we can rearrange to get;
z = -1 - 3x
Putting -1 - 3x for z in eq(1) and (eq 3),we have;
(x + 3(-1 - 3x)) - y = 2
x -3 - 9x - y = 2
-8x - y = 2 + 3
-8x - y = 5
y = -5 - 8x
Putting y = -5 - 8x and z = -1 - 3x into eq(3), we have;
x + 3(-5 - 8x) + (-1 - 3x) = -16
x - 15 - 24x - 1 - 3x = -16
-26x - 16 = -16
-26x = 16 + 16
x = 0
Since y = -5 - 8x, then y = -5 - 8(0)
y = - 5
Also, since z = -1 - 3x, then;
z = -1 - 3(0)
z = -1
The sum of the three numbers are;
x + y + z = 0 + (-5) + (-1) = -6