Finding the Fourth Proportional to 2,613.08, 3,916.85 and 857.62

Step by Step Solution

1. Step 1: Write the proportion equation
   2,613.08 : 3,916.85 = 857.62 : x
2. Step 2: Convert to fraction form
   2,613.08/3,916.85 = 857.62/x
3. Step 3: Cross multiply
   2,613.08x = 3,916.85 × 857.62
4. Step 4: Simplify right side
   2,613.08x = 3,359,149.31
5. Step 5: Solve for x
   x = 3,359,149.31/2,613.08
6. Step 6: Final answer
   x = 1,285.52