Finding the Fourth Proportional to 12,155.50, 18,240.42 and 5,135.06

Step by Step Solution

1. Step 1: Write the proportion equation
   12,155.50 : 18,240.42 = 5,135.06 : x
2. Step 2: Convert to fraction form
   12,155.50/18,240.42 = 5,135.06/x
3. Step 3: Cross multiply
   12,155.50x = 18,240.42 × 5,135.06
4. Step 4: Simplify right side
   12,155.50x = 93,665,559.92
5. Step 5: Solve for x
   x = 93,665,559.92/12,155.50
6. Step 6: Final answer
   x = 7,705.61