<h3>
Answer: C) 81.5%</h3>
This value is approximate.
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Explanation:
We have a normal distribution with these parameters
- mu = 128 = population mean
- sigma = 30 = population standard deviation
The goal is to find the area under the curve from x = 68 to x = 158, where x is the number of text messages sent per day. So effectively, we want to find P(68 < x < 158).
Let's convert the score x = 68 to its corresponding z score
z = (x-mu)/sigma
z = (68-128)/30
z = -60/30
z = -2
This tells us that the score x = 68 is exactly two standard deviations below the mean mu = 128.
Repeat for x = 158
z = (x-mu)/sigma
z = (158-128)/30
z = 30/30
z = 1
This value is exactly one standard deviation above the mean
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The problem of finding P(68 < x < 158) can be rephrased into P(-2 < z < 1)
We do this because we can then use the Empirical rule as shown in the diagram below.
We'll focus on the regions between z = -2 and z = 1. This consists of the blue 13.5% on the left, and the two pink 34% portions. So we will say 13.5% + 34% + 34% = 81.5%
Approximately 81.5% of the the population sends between 68 and 158 text messages per day. This value is approximate because the percentages listed in the Empirical rule below are approximate.
Answer:
13 over 3
Step-by-step explanation:
Hi Jakeyriabryant! I hope you’re fine!
I hope I have understood the problem well.
If so, what the exercise raises is the following equality:
(x-1) / 5 = 2/3
From this equation you must clear the "x".
First, we pass the 5 that is dividing on the side of the x, to the other side and passes multiplying
(X – 1) / 5 = 2/3
(X – 1) = (2/3)*5
X – 1 = 10/3
Then we pass the one that is subtracting from the side of the x, to the other side and passes adding
X = 10/3 + 1
Remember that to add or subtract fractions they must have the same denominator or a common denominator (in this case we can write 1 as fraction 3/3). Then,
X = 10/3 + 3/3
X = 13/3
I hope I've been helpful!
Regards!
I believe the answer is
A is $45 billion
B is $60 billion
Answer:67.5
Step-by-step explanation:The question asked the HEIGHT. So multiply the scale factor (2.5) and the inches tall (27).