Finding the Fourth Proportional to 1,380.92, 1,905.74 and 791.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,380.92 : 1,905.74 = 791.56 : x
2. Step 2: Convert to fraction form
   1,380.92/1,905.74 = 791.56/x
3. Step 3: Cross multiply
   1,380.92x = 1,905.74 × 791.56
4. Step 4: Simplify right side
   1,380.92x = 1,508,507.55
5. Step 5: Solve for x
   x = 1,508,507.55/1,380.92
6. Step 6: Final answer
   x = 1,092.39