Finding the Fourth Proportional to 2,558.81, 3,530.55 and 1,439.53

Step by Step Solution

1. Step 1: Write the proportion equation
   2,558.81 : 3,530.55 = 1,439.53 : x
2. Step 2: Convert to fraction form
   2,558.81/3,530.55 = 1,439.53/x
3. Step 3: Cross multiply
   2,558.81x = 3,530.55 × 1,439.53
4. Step 4: Simplify right side
   2,558.81x = 5,082,332.64
5. Step 5: Solve for x
   x = 5,082,332.64/2,558.81
6. Step 6: Final answer
   x = 1,986.21