Finding the Fourth Proportional to 259,123.89, 388,667.09 and 81,681.69

Step by Step Solution

1. Step 1: Write the proportion equation
   259,123.89 : 388,667.09 = 81,681.69 : x
2. Step 2: Convert to fraction form
   259,123.89/388,667.09 = 81,681.69/x
3. Step 3: Cross multiply
   259,123.89x = 388,667.09 × 81,681.69
4. Step 4: Simplify right side
   259,123.89x = 31,746,984,350.17
5. Step 5: Solve for x
   x = 31,746,984,350.17/259,123.89
6. Step 6: Final answer
   x = 122,516.62