Finding the Fourth Proportional to 105,909.31, 146,211.59 and 81,657.30

Step by Step Solution

1. Step 1: Write the proportion equation
   105,909.31 : 146,211.59 = 81,657.30 : x
2. Step 2: Convert to fraction form
   105,909.31/146,211.59 = 81,657.30/x
3. Step 3: Cross multiply
   105,909.31x = 146,211.59 × 81,657.30
4. Step 4: Simplify right side
   105,909.31x = 11,939,243,668.11
5. Step 5: Solve for x
   x = 11,939,243,668.11/105,909.31
6. Step 6: Final answer
   x = 112,730.82