Finding the Fourth Proportional to 259,488, 389,406.69 and 91,009.89

Step by Step Solution

1. Step 1: Write the proportion equation
   259,488 : 389,406.69 = 91,009.89 : x
2. Step 2: Convert to fraction form
   259,488/389,406.69 = 91,009.89/x
3. Step 3: Cross multiply
   259,488x = 389,406.69 × 91,009.89
4. Step 4: Simplify right side
   259,488x = 35,439,860,022.16
5. Step 5: Solve for x
   x = 35,439,860,022.16/259,488
6. Step 6: Final answer
   x = 136,576.10