Answer:
The probability that <em>X</em> is less than 42 is 0.1271.
Step-by-step explanation:
The random variable <em>X </em>follows a Normal distribution.
The mean and standard deviation are:
E (X) = <em>μ</em> = 50.
SD (X) = <em>σ</em> = 7.
A normal distribution is continuous probability distribution.
The Normal probability distribution with mean µ and standard deviation σ is given by,

To compute the probability of a Normal random variable we first standardize the raw score.
The raw scores are standardized using the formula:

These standardized scores are known as <em>z</em>-scores and they follow normal distribution with mean 0 and standard deviation 1.
Compute the probability of (X < 42) as follows:

*Use a <em>z</em>-table for the probability.
Thus, the probability that <em>X</em> is less than 42 is 0.1271.
The normal curve is shown below.
Answer:
50
Step-by-step explanation:
75 dived into 3 parts can also be written as 75/3. 75/3 is 25 making each part worth 25. 2 segments are included in the marked portion so its 50 or (25 + 25)
the first simple interest will be $1.73 more than the second one.
<h3>
Which is the difference between the two interests?</h3>
The loan is of $575, and there are two options:
7 years at 4.5% or 8 years at 3.9%
Remember that the simple interest formula is:
SI = (P*R*T)/100
Where:
P = principal value.
R = rate (this is the percentage per year)
T = time, in years.
Then for the first option. the interest will be:
SI = ($575*4.5*7)/100 = $181.13
For the second option we will have the interest:
SI' =( $575*3.9*8)/100 = $179.4
The difference is:
$181.13 - $179.4 = $1.73
This means that the first simple interest will be $1.73 more than the second one.
If you want to learn more about simple interests:
brainly.com/question/20690803
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