Finding the Fourth Proportional to 665,412.50, 998,404.78 and 216,271.10

Step by Step Solution

1. Step 1: Write the proportion equation
   665,412.50 : 998,404.78 = 216,271.10 : x
2. Step 2: Convert to fraction form
   665,412.50/998,404.78 = 216,271.10/x
3. Step 3: Cross multiply
   665,412.50x = 998,404.78 × 216,271.10
4. Step 4: Simplify right side
   665,412.50x = 215,926,100,015.86
5. Step 5: Solve for x
   x = 215,926,100,015.86/665,412.50
6. Step 6: Final answer
   x = 324,499.61