Finding the Fourth Proportional to 256,539.72, 354,018.69 and 143,384.34

Step by Step Solution

1. Step 1: Write the proportion equation
   256,539.72 : 354,018.69 = 143,384.34 : x
2. Step 2: Convert to fraction form
   256,539.72/354,018.69 = 143,384.34/x
3. Step 3: Cross multiply
   256,539.72x = 354,018.69 × 143,384.34
4. Step 4: Simplify right side
   256,539.72x = 50,760,736,213.31
5. Step 5: Solve for x
   x = 50,760,736,213.31/256,539.72
6. Step 6: Final answer
   x = 197,866.97