Finding the Fourth Proportional to 171,650.89, 257,433.25 and 81,638.06

Step by Step Solution

1. Step 1: Write the proportion equation
   171,650.89 : 257,433.25 = 81,638.06 : x
2. Step 2: Convert to fraction form
   171,650.89/257,433.25 = 81,638.06/x
3. Step 3: Cross multiply
   171,650.89x = 257,433.25 × 81,638.06
4. Step 4: Simplify right side
   171,650.89x = 21,016,351,109.50
5. Step 5: Solve for x
   x = 21,016,351,109.50/171,650.89
6. Step 6: Final answer
   x = 122,436.60