Finding the Fourth Proportional to 1,386.97, 2,077.59 and 691.54

Step by Step Solution

1. Step 1: Write the proportion equation
   1,386.97 : 2,077.59 = 691.54 : x
2. Step 2: Convert to fraction form
   1,386.97/2,077.59 = 691.54/x
3. Step 3: Cross multiply
   1,386.97x = 2,077.59 × 691.54
4. Step 4: Simplify right side
   1,386.97x = 1,436,736.59
5. Step 5: Solve for x
   x = 1,436,736.59/1,386.97
6. Step 6: Final answer
   x = 1,035.88