Finding the Fourth Proportional to 428,120.29, 641,756.01 and 238,667.31

Step by Step Solution

1. Step 1: Write the proportion equation
   428,120.29 : 641,756.01 = 238,667.31 : x
2. Step 2: Convert to fraction form
   428,120.29/641,756.01 = 238,667.31/x
3. Step 3: Cross multiply
   428,120.29x = 641,756.01 × 238,667.31
4. Step 4: Simplify right side
   428,120.29x = 153,166,181,478.04
5. Step 5: Solve for x
   x = 153,166,181,478.04/428,120.29
6. Step 6: Final answer
   x = 357,764.36