Finding the Fourth Proportional to 1,371.20, 1,892.38 and 781.93

Step by Step Solution

1. Step 1: Write the proportion equation
   1,371.20 : 1,892.38 = 781.93 : x
2. Step 2: Convert to fraction form
   1,371.20/1,892.38 = 781.93/x
3. Step 3: Cross multiply
   1,371.20x = 1,892.38 × 781.93
4. Step 4: Simplify right side
   1,371.20x = 1,479,708.69
5. Step 5: Solve for x
   x = 1,479,708.69/1,371.20
6. Step 6: Final answer
   x = 1,079.13