Finding the Fourth Proportional to 3,139.09, 4,710.80 and 1,191.31

Step by Step Solution

1. Step 1: Write the proportion equation
   3,139.09 : 4,710.80 = 1,191.31 : x
2. Step 2: Convert to fraction form
   3,139.09/4,710.80 = 1,191.31/x
3. Step 3: Cross multiply
   3,139.09x = 4,710.80 × 1,191.31
4. Step 4: Simplify right side
   3,139.09x = 5,612,023.15
5. Step 5: Solve for x
   x = 5,612,023.15/3,139.09
6. Step 6: Final answer
   x = 1,787.79