Finding the Fourth Proportional to 2,558.53, 3,530.84 and 1,439.40

Step by Step Solution

1. Step 1: Write the proportion equation
   2,558.53 : 3,530.84 = 1,439.40 : x
2. Step 2: Convert to fraction form
   2,558.53/3,530.84 = 1,439.40/x
3. Step 3: Cross multiply
   2,558.53x = 3,530.84 × 1,439.40
4. Step 4: Simplify right side
   2,558.53x = 5,082,291.10
5. Step 5: Solve for x
   x = 5,082,291.10/2,558.53
6. Step 6: Final answer
   x = 1,986.41