Finding the Fourth Proportional to 1,391.94, 1,920.50 and 1,096.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,391.94 : 1,920.50 = 1,096.30 : x
2. Step 2: Convert to fraction form
   1,391.94/1,920.50 = 1,096.30/x
3. Step 3: Cross multiply
   1,391.94x = 1,920.50 × 1,096.30
4. Step 4: Simplify right side
   1,391.94x = 2,105,444.15
5. Step 5: Solve for x
   x = 2,105,444.15/1,391.94
6. Step 6: Final answer
   x = 1,512.60