Finding the Fourth Proportional to 1,388.56, 1,916.39 and 791.27

Step by Step Solution

1. Step 1: Write the proportion equation
   1,388.56 : 1,916.39 = 791.27 : x
2. Step 2: Convert to fraction form
   1,388.56/1,916.39 = 791.27/x
3. Step 3: Cross multiply
   1,388.56x = 1,916.39 × 791.27
4. Step 4: Simplify right side
   1,388.56x = 1,516,376.80
5. Step 5: Solve for x
   x = 1,516,376.80/1,388.56
6. Step 6: Final answer
   x = 1,092.05