Given:
The given equation is
To find:
All the real solutions.
Solution:
We have,
It can be written as
Using zero product property, we get
and
and
and
We know that is an imaginary number because there is a negative sign under the square root.
Therefore, is the only real solution of the given equation.
Answer:
The z score for bolt of diameter 18.12 mm is 1.20.
Step-by-step explanation:
Let <em>X</em> = diameter of bolts.
It is provided that the random variable <em>X</em> follows a Normal distribution with mean, <em>μ</em> = 18 mm and standard deviation, <em>σ</em> = 0.10 mm.
A <em>z</em>-score is a standardized score, a numerical, that defines how far a data value from the mean.
The distribution of <em>z</em>-scores is defined by the Standard Normal distribution.
The formula to compute the <em>z</em>-score is:
The value of the diameter of a bolt is, <em>x</em> = 18.12 mm.
Compute the <em>z</em>-score for this value as follows:
Thus, the z score for bolt of diameter 18.12 mm is 1.20.