Finding the Fourth Proportional to 9,377.83, 12,940.87 and 5,128.11

Step by Step Solution

1. Step 1: Write the proportion equation
   9,377.83 : 12,940.87 = 5,128.11 : x
2. Step 2: Convert to fraction form
   9,377.83/12,940.87 = 5,128.11/x
3. Step 3: Cross multiply
   9,377.83x = 12,940.87 × 5,128.11
4. Step 4: Simplify right side
   9,377.83x = 66,362,204.86
5. Step 5: Solve for x
   x = 66,362,204.86/9,377.83
6. Step 6: Final answer
   x = 7,076.50