X = excellent condition books
y = fair condition books
2.50x + 0.50y <== ur expression
<span>We have this equation:
</span>

and we need to find the value of x.
First of all, we multiply the whole equation for 1/2, so our goal is to isolate x, therefore:
Next step we must do is to apply <span>logarithms:
</span>

Next, we have to apply identities and then to solve the equation:




Finally, we have the value of x which was our goal. This is the answer for the question above:
Answer:
a) 3.128
b) Yes, it is an outerlier
Step-by-step explanation:
The standardized z-score for a particular sample can be determined via the following expression:
z_i = {x_i -\bar x}/{s}
Where;
\bar x = sample means
s = sample standard deviation
Given data:
the mean shipment thickness (\bar x) = 0.2731 mm
With the standardized deviation (s) = 0.000959 mm
The standardized z-score for a certain shipment with a diameter x_i= 0.2761 mm can be determined via the following previous expression
z_i = {x_i -\bar x}/{s}
z_i = {0.2761-0.2731}/{ 0.000959}
z_i = 3.128
b)
From the standardized z-score
If [z_i < 2]; it typically implies that the data is unusual
If [z_i > 2]; it means that the data value is an outerlier
However, since our z_i > 3 (I.e it is 3.128), we conclude that it is an outerlier.