Finding the Fourth Proportional to 663,036.96, 915,100.74 and 391,171.32

Step by Step Solution

1. Step 1: Write the proportion equation
   663,036.96 : 915,100.74 = 391,171.32 : x
2. Step 2: Convert to fraction form
   663,036.96/915,100.74 = 391,171.32/x
3. Step 3: Cross multiply
   663,036.96x = 915,100.74 × 391,171.32
4. Step 4: Simplify right side
   663,036.96x = 357,961,164,398.78
5. Step 5: Solve for x
   x = 357,961,164,398.78/663,036.96
6. Step 6: Final answer
   x = 539,881.16