Finding the Fourth Proportional to 5,158.72, 7,168.42 and 5,105.20

Step by Step Solution

1. Step 1: Write the proportion equation
   5,158.72 : 7,168.42 = 5,105.20 : x
2. Step 2: Convert to fraction form
   5,158.72/7,168.42 = 5,105.20/x
3. Step 3: Cross multiply
   5,158.72x = 7,168.42 × 5,105.20
4. Step 4: Simplify right side
   5,158.72x = 36,596,217.78
5. Step 5: Solve for x
   x = 36,596,217.78/5,158.72
6. Step 6: Final answer
   x = 7,094.05