Finding the Fourth Proportional to 2,586.87, 3,878.79 and 1,025.60

Step by Step Solution

1. Step 1: Write the proportion equation
   2,586.87 : 3,878.79 = 1,025.60 : x
2. Step 2: Convert to fraction form
   2,586.87/3,878.79 = 1,025.60/x
3. Step 3: Cross multiply
   2,586.87x = 3,878.79 × 1,025.60
4. Step 4: Simplify right side
   2,586.87x = 3,978,067.63
5. Step 5: Solve for x
   x = 3,978,067.63/2,586.87
6. Step 6: Final answer
   x = 1,537.79