Finding the Fourth Proportional to 1,367.88, 1,887.77 and 778.60

Step by Step Solution

1. Step 1: Write the proportion equation
   1,367.88 : 1,887.77 = 778.60 : x
2. Step 2: Convert to fraction form
   1,367.88/1,887.77 = 778.60/x
3. Step 3: Cross multiply
   1,367.88x = 1,887.77 × 778.60
4. Step 4: Simplify right side
   1,367.88x = 1,469,817.72
5. Step 5: Solve for x
   x = 1,469,817.72/1,367.88
6. Step 6: Final answer
   x = 1,074.52