Finding the Fourth Proportional to 2,568.72, 3,853.22 and 813.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,568.72 : 3,853.22 = 813.78 : x
2. Step 2: Convert to fraction form
   2,568.72/3,853.22 = 813.78/x
3. Step 3: Cross multiply
   2,568.72x = 3,853.22 × 813.78
4. Step 4: Simplify right side
   2,568.72x = 3,135,673.37
5. Step 5: Solve for x
   x = 3,135,673.37/2,568.72
6. Step 6: Final answer
   x = 1,220.71