Finding the Fourth Proportional to 113,128.25, 155,989.04 and 72,238.61

Step by Step Solution

1. Step 1: Write the proportion equation
   113,128.25 : 155,989.04 = 72,238.61 : x
2. Step 2: Convert to fraction form
   113,128.25/155,989.04 = 72,238.61/x
3. Step 3: Cross multiply
   113,128.25x = 155,989.04 × 72,238.61
4. Step 4: Simplify right side
   113,128.25x = 11,268,430,644.89
5. Step 5: Solve for x
   x = 11,268,430,644.89/113,128.25
6. Step 6: Final answer
   x = 99,607.58