Finding the Fourth Proportional to 1,399.43, 1,931.54 and 810.29

Step by Step Solution

1. Step 1: Write the proportion equation
   1,399.43 : 1,931.54 = 810.29 : x
2. Step 2: Convert to fraction form
   1,399.43/1,931.54 = 810.29/x
3. Step 3: Cross multiply
   1,399.43x = 1,931.54 × 810.29
4. Step 4: Simplify right side
   1,399.43x = 1,565,093.84
5. Step 5: Solve for x
   x = 1,565,093.84/1,399.43
6. Step 6: Final answer
   x = 1,118.38