Finding the Fourth Proportional to 2,728.10, 4,092.12 and 780.29

Step by Step Solution

1. Step 1: Write the proportion equation
   2,728.10 : 4,092.12 = 780.29 : x
2. Step 2: Convert to fraction form
   2,728.10/4,092.12 = 780.29/x
3. Step 3: Cross multiply
   2,728.10x = 4,092.12 × 780.29
4. Step 4: Simplify right side
   2,728.10x = 3,193,040.31
5. Step 5: Solve for x
   x = 3,193,040.31/2,728.10
6. Step 6: Final answer
   x = 1,170.43