Finding the Fourth Proportional to 8,518.91, 12,779.71 and 3,840.55

Step by Step Solution

1. Step 1: Write the proportion equation
   8,518.91 : 12,779.71 = 3,840.55 : x
2. Step 2: Convert to fraction form
   8,518.91/12,779.71 = 3,840.55/x
3. Step 3: Cross multiply
   8,518.91x = 12,779.71 × 3,840.55
4. Step 4: Simplify right side
   8,518.91x = 49,081,073.69
5. Step 5: Solve for x
   x = 49,081,073.69/8,518.91
6. Step 6: Final answer
   x = 5,761.43