Finding the Fourth Proportional to 638,633.04, 957,978.72 and 217,912.56

Step by Step Solution

1. Step 1: Write the proportion equation
   638,633.04 : 957,978.72 = 217,912.56 : x
2. Step 2: Convert to fraction form
   638,633.04/957,978.72 = 217,912.56/x
3. Step 3: Cross multiply
   638,633.04x = 957,978.72 × 217,912.56
4. Step 4: Simplify right side
   638,633.04x = 208,755,595,300.72
5. Step 5: Solve for x
   x = 208,755,595,300.72/638,633.04
6. Step 6: Final answer
   x = 326,878.79