Finding the Fourth Proportional to 639,128.78, 882,016.18 and 352,667.32

Step by Step Solution

1. Step 1: Write the proportion equation
   639,128.78 : 882,016.18 = 352,667.32 : x
2. Step 2: Convert to fraction form
   639,128.78/882,016.18 = 352,667.32/x
3. Step 3: Cross multiply
   639,128.78x = 882,016.18 × 352,667.32
4. Step 4: Simplify right side
   639,128.78x = 311,058,282,397.24
5. Step 5: Solve for x
   x = 311,058,282,397.24/639,128.78
6. Step 6: Final answer
   x = 486,691.09