Finding the Fourth Proportional to 398,882.72, 550,459.92 and 217,598.72

Step by Step Solution

1. Step 1: Write the proportion equation
   398,882.72 : 550,459.92 = 217,598.72 : x
2. Step 2: Convert to fraction form
   398,882.72/550,459.92 = 217,598.72/x
3. Step 3: Cross multiply
   398,882.72x = 550,459.92 × 217,598.72
4. Step 4: Simplify right side
   398,882.72x = 119,779,374,003.30
5. Step 5: Solve for x
   x = 119,779,374,003.30/398,882.72
6. Step 6: Final answer
   x = 300,287.20