Finding the Fourth Proportional to 604,915.30, 907,664.55 and 427,039.30

Step by Step Solution

1. Step 1: Write the proportion equation
   604,915.30 : 907,664.55 = 427,039.30 : x
2. Step 2: Convert to fraction form
   604,915.30/907,664.55 = 427,039.30/x
3. Step 3: Cross multiply
   604,915.30x = 907,664.55 × 427,039.30
4. Step 4: Simplify right side
   604,915.30x = 387,608,434,066.82
5. Step 5: Solve for x
   x = 387,608,434,066.82/604,915.30
6. Step 6: Final answer
   x = 640,764.80