Finding the Fourth Proportional to 71,921.29, 99,249.31 and 40,089.50

Step by Step Solution

1. Step 1: Write the proportion equation
   71,921.29 : 99,249.31 = 40,089.50 : x
2. Step 2: Convert to fraction form
   71,921.29/99,249.31 = 40,089.50/x
3. Step 3: Cross multiply
   71,921.29x = 99,249.31 × 40,089.50
4. Step 4: Simplify right side
   71,921.29x = 3,978,855,511.48
5. Step 5: Solve for x
   x = 3,978,855,511.48/71,921.29
6. Step 6: Final answer
   x = 55,322.36