Finding the Fourth Proportional to 72,309.08, 99,716.43 and 56,387.72

Step by Step Solution

1. Step 1: Write the proportion equation
   72,309.08 : 99,716.43 = 56,387.72 : x
2. Step 2: Convert to fraction form
   72,309.08/99,716.43 = 56,387.72/x
3. Step 3: Cross multiply
   72,309.08x = 99,716.43 × 56,387.72
4. Step 4: Simplify right side
   72,309.08x = 5,622,782,134.24
5. Step 5: Solve for x
   x = 5,622,782,134.24/72,309.08
6. Step 6: Final answer
   x = 77,760.39