Finding the Fourth Proportional to 9,115.43, 12,578.83 and 5,136.77

Step by Step Solution

1. Step 1: Write the proportion equation
   9,115.43 : 12,578.83 = 5,136.77 : x
2. Step 2: Convert to fraction form
   9,115.43/12,578.83 = 5,136.77/x
3. Step 3: Cross multiply
   9,115.43x = 12,578.83 × 5,136.77
4. Step 4: Simplify right side
   9,115.43x = 64,614,575.18
5. Step 5: Solve for x
   x = 64,614,575.18/9,115.43
6. Step 6: Final answer
   x = 7,088.49