Finding the Fourth Proportional to 2,599.39, 3,899.54 and 1,139.57

Step by Step Solution

1. Step 1: Write the proportion equation
   2,599.39 : 3,899.54 = 1,139.57 : x
2. Step 2: Convert to fraction form
   2,599.39/3,899.54 = 1,139.57/x
3. Step 3: Cross multiply
   2,599.39x = 3,899.54 × 1,139.57
4. Step 4: Simplify right side
   2,599.39x = 4,443,796.77
5. Step 5: Solve for x
   x = 4,443,796.77/2,599.39
6. Step 6: Final answer
   x = 1,709.55