Finding the Fourth Proportional to 428,925.31, 591,987.89 and 238,000.21

Step by Step Solution

1. Step 1: Write the proportion equation
   428,925.31 : 591,987.89 = 238,000.21 : x
2. Step 2: Convert to fraction form
   428,925.31/591,987.89 = 238,000.21/x
3. Step 3: Cross multiply
   428,925.31x = 591,987.89 × 238,000.21
4. Step 4: Simplify right side
   428,925.31x = 140,893,242,137.46
5. Step 5: Solve for x
   x = 140,893,242,137.46/428,925.31
6. Step 6: Final answer
   x = 328,479.66