Finding the Fourth Proportional to 259,013.78, 388,569.88 and 90,581.98

Step by Step Solution

1. Step 1: Write the proportion equation
   259,013.78 : 388,569.88 = 90,581.98 : x
2. Step 2: Convert to fraction form
   259,013.78/388,569.88 = 90,581.98/x
3. Step 3: Cross multiply
   259,013.78x = 388,569.88 × 90,581.98
4. Step 4: Simplify right side
   259,013.78x = 35,197,429,098.76
5. Step 5: Solve for x
   x = 35,197,429,098.76/259,013.78
6. Step 6: Final answer
   x = 135,890.18