Finding the Fourth Proportional to 2,815.90, 3,885.89 and 1,557

Step by Step Solution

1. Step 1: Write the proportion equation
   2,815.90 : 3,885.89 = 1,557 : x
2. Step 2: Convert to fraction form
   2,815.90/3,885.89 = 1,557/x
3. Step 3: Cross multiply
   2,815.90x = 3,885.89 × 1,557
4. Step 4: Simplify right side
   2,815.90x = 6,050,330.73
5. Step 5: Solve for x
   x = 6,050,330.73/2,815.90
6. Step 6: Final answer
   x = 2,148.63