Finding the Fourth Proportional to 7,111.96, 9,815.50 and 5,129.08

Step by Step Solution

1. Step 1: Write the proportion equation
   7,111.96 : 9,815.50 = 5,129.08 : x
2. Step 2: Convert to fraction form
   7,111.96/9,815.50 = 5,129.08/x
3. Step 3: Cross multiply
   7,111.96x = 9,815.50 × 5,129.08
4. Step 4: Simplify right side
   7,111.96x = 50,344,484.74
5. Step 5: Solve for x
   x = 50,344,484.74/7,111.96
6. Step 6: Final answer
   x = 7,078.85