Finding the Fourth Proportional to 72,123.92, 99,530.76 and 39,857.64

Step by Step Solution

1. Step 1: Write the proportion equation
   72,123.92 : 99,530.76 = 39,857.64 : x
2. Step 2: Convert to fraction form
   72,123.92/99,530.76 = 39,857.64/x
3. Step 3: Cross multiply
   72,123.92x = 99,530.76 × 39,857.64
4. Step 4: Simplify right side
   72,123.92x = 3,967,061,201.01
5. Step 5: Solve for x
   x = 3,967,061,201.01/72,123.92
6. Step 6: Final answer
   x = 55,003.41