Finding the Fourth Proportional to 2,580.57, 3,871.16 and 849.20

Step by Step Solution

1. Step 1: Write the proportion equation
   2,580.57 : 3,871.16 = 849.20 : x
2. Step 2: Convert to fraction form
   2,580.57/3,871.16 = 849.20/x
3. Step 3: Cross multiply
   2,580.57x = 3,871.16 × 849.20
4. Step 4: Simplify right side
   2,580.57x = 3,287,365.47
5. Step 5: Solve for x
   x = 3,287,365.47/2,580.57
6. Step 6: Final answer
   x = 1,273.89