Finding the Fourth Proportional to 1,381.15, 1,905.88 and 791.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,381.15 : 1,905.88 = 791.72 : x
2. Step 2: Convert to fraction form
   1,381.15/1,905.88 = 791.72/x
3. Step 3: Cross multiply
   1,381.15x = 1,905.88 × 791.72
4. Step 4: Simplify right side
   1,381.15x = 1,508,931.16
5. Step 5: Solve for x
   x = 1,508,931.16/1,381.15
6. Step 6: Final answer
   x = 1,092.52