Finding the Fourth Proportional to 8,757.69, 12,085.40 and 4,778.80

Step by Step Solution

1. Step 1: Write the proportion equation
   8,757.69 : 12,085.40 = 4,778.80 : x
2. Step 2: Convert to fraction form
   8,757.69/12,085.40 = 4,778.80/x
3. Step 3: Cross multiply
   8,757.69x = 12,085.40 × 4,778.80
4. Step 4: Simplify right side
   8,757.69x = 57,753,691.25
5. Step 5: Solve for x
   x = 57,753,691.25/8,757.69
6. Step 6: Final answer
   x = 6,594.63