Short Answer 
The process to find the difference in hours between online (y) and on-site (z) training involves understanding and rearranging the equation 10z + 15y = 85 to solve for y as y = (85 – 10z) / 15. The difference in hours is then calculated using the formula Difference = ((85 – 10z) / 15) – z.
Step 1: Understand the Equation
To find the difference in hours between online and on-site training courses, we start by examining the given equation: 10z + 15y = 85. This equation relates the hours for online courses (y) and on-site courses (z). Our aim is to rearrange this equation to express y in terms of z.
Step 2: Rearranging the Equation
Next, we need to solve for y by isolating it in the equation. Follow these steps:
- Subtract 10z from both sides: 15y = 85 – 10z
- Divide the entire equation by 15 to find y: y = (85 – 10z) / 15
This gives us the hours required for online courses in terms of the hours for on-site courses.
Step 3: Calculate the Difference
To find the difference in hours between online and on-site training, we subtract z from y. The formula becomes:
- Difference = y – z
- Substituting for y gives: Difference = ((85 – 10z) / 15) – z
This result will give us the specific difference in hours between each online and on-site training course.