Finding the Fourth Proportional to 285,540.72, 428,312.04 and 72,308.55

Step by Step Solution

1. Step 1: Write the proportion equation
   285,540.72 : 428,312.04 = 72,308.55 : x
2. Step 2: Convert to fraction form
   285,540.72/428,312.04 = 72,308.55/x
3. Step 3: Cross multiply
   285,540.72x = 428,312.04 × 72,308.55
4. Step 4: Simplify right side
   285,540.72x = 30,970,622,559.94
5. Step 5: Solve for x
   x = 30,970,622,559.94/285,540.72
6. Step 6: Final answer
   x = 108,463.07