Finding the Fourth Proportional to 1,371.08, 1,892.18 and 781.68

Step by Step Solution

1. Step 1: Write the proportion equation
   1,371.08 : 1,892.18 = 781.68 : x
2. Step 2: Convert to fraction form
   1,371.08/1,892.18 = 781.68/x
3. Step 3: Cross multiply
   1,371.08x = 1,892.18 × 781.68
4. Step 4: Simplify right side
   1,371.08x = 1,479,079.26
5. Step 5: Solve for x
   x = 1,479,079.26/1,371.08
6. Step 6: Final answer
   x = 1,078.77