Finding the Fourth Proportional to 1,389.27, 1,917.03 and 791.55

Step by Step Solution

1. Step 1: Write the proportion equation
   1,389.27 : 1,917.03 = 791.55 : x
2. Step 2: Convert to fraction form
   1,389.27/1,917.03 = 791.55/x
3. Step 3: Cross multiply
   1,389.27x = 1,917.03 × 791.55
4. Step 4: Simplify right side
   1,389.27x = 1,517,425.10
5. Step 5: Solve for x
   x = 1,517,425.10/1,389.27
6. Step 6: Final answer
   x = 1,092.25