Finding the Fourth Proportional to 105,469.30, 157,973.55 and 81,910.90

Step by Step Solution

1. Step 1: Write the proportion equation
   105,469.30 : 157,973.55 = 81,910.90 : x
2. Step 2: Convert to fraction form
   105,469.30/157,973.55 = 81,910.90/x
3. Step 3: Cross multiply
   105,469.30x = 157,973.55 × 81,910.90
4. Step 4: Simplify right side
   105,469.30x = 12,939,755,656.70
5. Step 5: Solve for x
   x = 12,939,755,656.70/105,469.30
6. Step 6: Final answer
   x = 122,687.41