Finding the Fourth Proportional to 72,387.97, 99,898.15 and 40,555.78

Step by Step Solution

1. Step 1: Write the proportion equation
   72,387.97 : 99,898.15 = 40,555.78 : x
2. Step 2: Convert to fraction form
   72,387.97/99,898.15 = 40,555.78/x
3. Step 3: Cross multiply
   72,387.97x = 99,898.15 × 40,555.78
4. Step 4: Simplify right side
   72,387.97x = 4,051,447,393.81
5. Step 5: Solve for x
   x = 4,051,447,393.81/72,387.97
6. Step 6: Final answer
   x = 55,968.52