Finding the Fourth Proportional to 1,367.80, 1,887.71 and 770.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,367.80 : 1,887.71 = 770.31 : x
2. Step 2: Convert to fraction form
   1,367.80/1,887.71 = 770.31/x
3. Step 3: Cross multiply
   1,367.80x = 1,887.71 × 770.31
4. Step 4: Simplify right side
   1,367.80x = 1,454,121.89
5. Step 5: Solve for x
   x = 1,454,121.89/1,367.80
6. Step 6: Final answer
   x = 1,063.11