If $$ y $$ varies jointly with $$ x $$ and $$ z $$ , the rel...

Question Analysis
This problem assesses the understanding of joint variation and the ability to find the constant of variation.

Key Concept Explanation
In joint variation, varies directly as the product of and . The relationship is given by , where is the constant of variation.

Step-by-step Solution
1. Start with the given equation:
2. Substitute the given values: