Answer:
The value of <em>n </em>is 15.
Step-by-step explanation:
The combined proportion is computed using the formula:

The information provided is as follows:

Compute the value of <em>n</em> as follows:


Thus, the value of <em>n </em>is 15.
The correct answer is the 3rd option !! good luck
The answer i do believe is 1/2