Finding the Fourth Proportional to 425,875.46, 638,025.86 and 215,009.78

Step by Step Solution

1. Step 1: Write the proportion equation
   425,875.46 : 638,025.86 = 215,009.78 : x
2. Step 2: Convert to fraction form
   425,875.46/638,025.86 = 215,009.78/x
3. Step 3: Cross multiply
   425,875.46x = 638,025.86 × 215,009.78
4. Step 4: Simplify right side
   425,875.46x = 137,181,797,140.31
5. Step 5: Solve for x
   x = 137,181,797,140.31/425,875.46
6. Step 6: Final answer
   x = 322,117.17