Finding the Fourth Proportional to 128,687.06, 177,593.02 and 72,096.50

Step by Step Solution

1. Step 1: Write the proportion equation
   128,687.06 : 177,593.02 = 72,096.50 : x
2. Step 2: Convert to fraction form
   128,687.06/177,593.02 = 72,096.50/x
3. Step 3: Cross multiply
   128,687.06x = 177,593.02 × 72,096.50
4. Step 4: Simplify right side
   128,687.06x = 12,803,835,166.43
5. Step 5: Solve for x
   x = 12,803,835,166.43/128,687.06
6. Step 6: Final answer
   x = 99,495.90