Finding the Fourth Proportional to 257,287.72, 355,057.05 and 156,685.72

Step by Step Solution

1. Step 1: Write the proportion equation
   257,287.72 : 355,057.05 = 156,685.72 : x
2. Step 2: Convert to fraction form
   257,287.72/355,057.05 = 156,685.72/x
3. Step 3: Cross multiply
   257,287.72x = 355,057.05 × 156,685.72
4. Step 4: Simplify right side
   257,287.72x = 55,632,369,520.33
5. Step 5: Solve for x
   x = 55,632,369,520.33/257,287.72
6. Step 6: Final answer
   x = 216,226.29