Finding the Fourth Proportional to 2,599.90, 3,899.27 and 1,039.61

Step by Step Solution

1. Step 1: Write the proportion equation
   2,599.90 : 3,899.27 = 1,039.61 : x
2. Step 2: Convert to fraction form
   2,599.90/3,899.27 = 1,039.61/x
3. Step 3: Cross multiply
   2,599.90x = 3,899.27 × 1,039.61
4. Step 4: Simplify right side
   2,599.90x = 4,053,732.43
5. Step 5: Solve for x
   x = 4,053,732.43/2,599.90
6. Step 6: Final answer
   x = 1,559.19