Finding the Fourth Proportional to 397,196.78, 548,119.89 and 215,904.05

Step by Step Solution

1. Step 1: Write the proportion equation
   397,196.78 : 548,119.89 = 215,904.05 : x
2. Step 2: Convert to fraction form
   397,196.78/548,119.89 = 215,904.05/x
3. Step 3: Cross multiply
   397,196.78x = 548,119.89 × 215,904.05
4. Step 4: Simplify right side
   397,196.78x = 118,341,304,136.55
5. Step 5: Solve for x
   x = 118,341,304,136.55/397,196.78
6. Step 6: Final answer
   x = 297,941.25