Finding the Fourth Proportional to 71,306.55, 106,951.59 and 18,720.15

Step by Step Solution

1. Step 1: Write the proportion equation
   71,306.55 : 106,951.59 = 18,720.15 : x
2. Step 2: Convert to fraction form
   71,306.55/106,951.59 = 18,720.15/x
3. Step 3: Cross multiply
   71,306.55x = 106,951.59 × 18,720.15
4. Step 4: Simplify right side
   71,306.55x = 2,002,149,807.54
5. Step 5: Solve for x
   x = 2,002,149,807.54/71,306.55
6. Step 6: Final answer
   x = 28,078.06