Finding the Fourth Proportional to 1,371.30, 1,892.52 and 781.68

Step by Step Solution

1. Step 1: Write the proportion equation
   1,371.30 : 1,892.52 = 781.68 : x
2. Step 2: Convert to fraction form
   1,371.30/1,892.52 = 781.68/x
3. Step 3: Cross multiply
   1,371.30x = 1,892.52 × 781.68
4. Step 4: Simplify right side
   1,371.30x = 1,479,345.03
5. Step 5: Solve for x
   x = 1,479,345.03/1,371.30
6. Step 6: Final answer
   x = 1,078.79