Finding the Fourth Proportional to 2,385.56, 3,292.38 and 1,391.40

Step by Step Solution

1. Step 1: Write the proportion equation
   2,385.56 : 3,292.38 = 1,391.40 : x
2. Step 2: Convert to fraction form
   2,385.56/3,292.38 = 1,391.40/x
3. Step 3: Cross multiply
   2,385.56x = 3,292.38 × 1,391.40
4. Step 4: Simplify right side
   2,385.56x = 4,581,017.53
5. Step 5: Solve for x
   x = 4,581,017.53/2,385.56
6. Step 6: Final answer
   x = 1,920.31