Finding the Fourth Proportional to 256,490.10, 384,776.50 and 78,997.05

Step by Step Solution

1. Step 1: Write the proportion equation
   256,490.10 : 384,776.50 = 78,997.05 : x
2. Step 2: Convert to fraction form
   256,490.10/384,776.50 = 78,997.05/x
3. Step 3: Cross multiply
   256,490.10x = 384,776.50 × 78,997.05
4. Step 4: Simplify right side
   256,490.10x = 30,396,208,409.33
5. Step 5: Solve for x
   x = 30,396,208,409.33/256,490.10
6. Step 6: Final answer
   x = 118,508.31