Finding the Fourth Proportional to 2,542.20, 3,813.15 and 810.69

Step by Step Solution

1. Step 1: Write the proportion equation
   2,542.20 : 3,813.15 = 810.69 : x
2. Step 2: Convert to fraction form
   2,542.20/3,813.15 = 810.69/x
3. Step 3: Cross multiply
   2,542.20x = 3,813.15 × 810.69
4. Step 4: Simplify right side
   2,542.20x = 3,091,282.57
5. Step 5: Solve for x
   x = 3,091,282.57/2,542.20
6. Step 6: Final answer
   x = 1,215.99