Answer:
4
Step-by-step explanation:
=
=4
Answer:

f(x) = 4 when x is 8
Step-by-step explanation:
Domain is the set of x values that make the function defined. Allowed x values for the function (mapping).
The Range is the set of y values that make the function defined. Allowed y values for the function (mapping).
- Whenever we need to find f(a), suppose, then we look for "a" in the domain and see its corresponding value mapping in the range.
- Whenever we will be given a value for f(x) = a, suppose, and we have to find "x", we look at the value a in the range and find corresponding x value in the domain.
Firstly, we need f(4), so we look for "4" in domain and see which number it corresponds to in range.
That is 
Thus,

Next,
We want "x" value that gives us a "y" value of 4. We look for "4" in the range and see which value it corresponds to. That is "8". So,
f(8) = 4
Answer:
- P(x < 84) = 0.3085 or approximately 31%
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<em>Hello to you from Brainly team!</em>
<h3>Given</h3>
- Mean grade μ = 86,
- Standard deviation σ = 4,
- Grade limit x = 84.
<h3>To find </h3>
- Probability of that a randomly selected grade is less than 84 or P(x < 84).
<h3>Solution</h3>
Find z-score using relevant equation:
Substitute values and calculate:
Using the z-score table find the corresponding P- value.
- P(x < 84) = 0.30854 or approximately 31%