Finding the Fourth Proportional to 2,231.38, 3,078.73 and 1,392.49

Step by Step Solution

1. Step 1: Write the proportion equation
   2,231.38 : 3,078.73 = 1,392.49 : x
2. Step 2: Convert to fraction form
   2,231.38/3,078.73 = 1,392.49/x
3. Step 3: Cross multiply
   2,231.38x = 3,078.73 × 1,392.49
4. Step 4: Simplify right side
   2,231.38x = 4,287,094.78
5. Step 5: Solve for x
   x = 4,287,094.78/2,231.38
6. Step 6: Final answer
   x = 1,921.28