Finding the Fourth Proportional to 1,367.87, 1,887.71 and 778.39

Step by Step Solution

1. Step 1: Write the proportion equation
   1,367.87 : 1,887.71 = 778.39 : x
2. Step 2: Convert to fraction form
   1,367.87/1,887.71 = 778.39/x
3. Step 3: Cross multiply
   1,367.87x = 1,887.71 × 778.39
4. Step 4: Simplify right side
   1,367.87x = 1,469,365.98
5. Step 5: Solve for x
   x = 1,469,365.98/1,367.87
6. Step 6: Final answer
   x = 1,074.20