Finding the Fourth Proportional to 8,640.72, 11,925.15 and 4,863.99

Step by Step Solution

1. Step 1: Write the proportion equation
   8,640.72 : 11,925.15 = 4,863.99 : x
2. Step 2: Convert to fraction form
   8,640.72/11,925.15 = 4,863.99/x
3. Step 3: Cross multiply
   8,640.72x = 11,925.15 × 4,863.99
4. Step 4: Simplify right side
   8,640.72x = 58,003,810.35
5. Step 5: Solve for x
   x = 58,003,810.35/8,640.72
6. Step 6: Final answer
   x = 6,712.84