Finding the Fourth Proportional to 2,558.49, 3,530.81 and 1,439.63

Step by Step Solution

1. Step 1: Write the proportion equation
   2,558.49 : 3,530.81 = 1,439.63 : x
2. Step 2: Convert to fraction form
   2,558.49/3,530.81 = 1,439.63/x
3. Step 3: Cross multiply
   2,558.49x = 3,530.81 × 1,439.63
4. Step 4: Simplify right side
   2,558.49x = 5,083,035.15
5. Step 5: Solve for x
   x = 5,083,035.15/2,558.49
6. Step 6: Final answer
   x = 1,986.73