Finding the Fourth Proportional to 115,978.89, 159,940.67 and 75,679.77

Step by Step Solution

1. Step 1: Write the proportion equation
   115,978.89 : 159,940.67 = 75,679.77 : x
2. Step 2: Convert to fraction form
   115,978.89/159,940.67 = 75,679.77/x
3. Step 3: Cross multiply
   115,978.89x = 159,940.67 × 75,679.77
4. Step 4: Simplify right side
   115,978.89x = 12,104,272,740.85
5. Step 5: Solve for x
   x = 12,104,272,740.85/115,978.89
6. Step 6: Final answer
   x = 104,366.17