Finding the Fourth Proportional to 8,697.60, 12,002.87 and 4,920.78

Step by Step Solution

1. Step 1: Write the proportion equation
   8,697.60 : 12,002.87 = 4,920.78 : x
2. Step 2: Convert to fraction form
   8,697.60/12,002.87 = 4,920.78/x
3. Step 3: Cross multiply
   8,697.60x = 12,002.87 × 4,920.78
4. Step 4: Simplify right side
   8,697.60x = 59,063,458.03
5. Step 5: Solve for x
   x = 59,063,458.03/8,697.60
6. Step 6: Final answer
   x = 6,790.78