Finding the Fourth Proportional to 2,403.78, 3,606.18 and 864.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,403.78 : 3,606.18 = 864.78 : x
2. Step 2: Convert to fraction form
   2,403.78/3,606.18 = 864.78/x
3. Step 3: Cross multiply
   2,403.78x = 3,606.18 × 864.78
4. Step 4: Simplify right side
   2,403.78x = 3,118,552.34
5. Step 5: Solve for x
   x = 3,118,552.34/2,403.78
6. Step 6: Final answer
   x = 1,297.35