Finding the Fourth Proportional to 1,411.29, 1,947.55 and 781.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,411.29 : 1,947.55 = 781.80 : x
2. Step 2: Convert to fraction form
   1,411.29/1,947.55 = 781.80/x
3. Step 3: Cross multiply
   1,411.29x = 1,947.55 × 781.80
4. Step 4: Simplify right side
   1,411.29x = 1,522,584.85
5. Step 5: Solve for x
   x = 1,522,584.85/1,411.29
6. Step 6: Final answer
   x = 1,078.86