Finding the Fourth Proportional to 1,367.72, 1,887.47 and 778.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,367.72 : 1,887.47 = 778.31 : x
2. Step 2: Convert to fraction form
   1,367.72/1,887.47 = 778.31/x
3. Step 3: Cross multiply
   1,367.72x = 1,887.47 × 778.31
4. Step 4: Simplify right side
   1,367.72x = 1,469,033.44
5. Step 5: Solve for x
   x = 1,469,033.44/1,367.72
6. Step 6: Final answer
   x = 1,074.08