Finding the Fourth Proportional to 2,561.09, 3,842.31 and 806.15

Step by Step Solution

1. Step 1: Write the proportion equation
   2,561.09 : 3,842.31 = 806.15 : x
2. Step 2: Convert to fraction form
   2,561.09/3,842.31 = 806.15/x
3. Step 3: Cross multiply
   2,561.09x = 3,842.31 × 806.15
4. Step 4: Simplify right side
   2,561.09x = 3,097,488.57
5. Step 5: Solve for x
   x = 3,097,488.57/2,561.09
6. Step 6: Final answer
   x = 1,209.44