Q:

A pharmacy claims that the average medication costs $32 but it could differ as much as $8. Write and solve an absolute value inequality to determine the range of medication costs at this pharmacy.

Accepted Solution

A:
A) |x − 32| ≥ 8; The medication costs range from $24 to $40
B)|x − 32| ≥ 8; The medications cost less than $24 or greater than $40.
C) |x − 32| ≤ 8; The medication costs range from $24 to $40
D) |x − 32| ≤8; The medications cost less than $24 or greater than $40.

So,

We can tell that the most expensive medication costs $40 and the cheapest costs $24.  Thus, only options A and C are left.

To see which inequality is true, test a value, such as $30, in the equation in option C.

|30 - 32| ≤ 8
|-2| ≤ 8
2 ≤ 8

Option C is correct.