Finding the Fourth Proportional to 3,915.78, 5,404.31 and 2,404.23

Step by Step Solution

1. Step 1: Write the proportion equation
   3,915.78 : 5,404.31 = 2,404.23 : x
2. Step 2: Convert to fraction form
   3,915.78/5,404.31 = 2,404.23/x
3. Step 3: Cross multiply
   3,915.78x = 5,404.31 × 2,404.23
4. Step 4: Simplify right side
   3,915.78x = 12,993,192.21
5. Step 5: Solve for x
   x = 12,993,192.21/3,915.78
6. Step 6: Final answer
   x = 3,318.16