Finding the Fourth Proportional to 1,139.39, 1,708.15 and 591.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,139.39 : 1,708.15 = 591.72 : x
2. Step 2: Convert to fraction form
   1,139.39/1,708.15 = 591.72/x
3. Step 3: Cross multiply
   1,139.39x = 1,708.15 × 591.72
4. Step 4: Simplify right side
   1,139.39x = 1,010,746.52
5. Step 5: Solve for x
   x = 1,010,746.52/1,139.39
6. Step 6: Final answer
   x = 887.09