Finding the Fourth Proportional to 498.10, 686.52 and 404.50

Step by Step Solution

1. Step 1: Write the proportion equation
   498.10 : 686.52 = 404.50 : x
2. Step 2: Convert to fraction form
   498.10/686.52 = 404.50/x
3. Step 3: Cross multiply
   498.10x = 686.52 × 404.50
4. Step 4: Simplify right side
   498.10x = 277,697.34
5. Step 5: Solve for x
   x = 277,697.34/498.10
6. Step 6: Final answer
   x = 557.51