Finding the Fourth Proportional to 2,728.24, 4,092.62 and 780.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,728.24 : 4,092.62 = 780.72 : x
2. Step 2: Convert to fraction form
   2,728.24/4,092.62 = 780.72/x
3. Step 3: Cross multiply
   2,728.24x = 4,092.62 × 780.72
4. Step 4: Simplify right side
   2,728.24x = 3,195,190.29
5. Step 5: Solve for x
   x = 3,195,190.29/2,728.24
6. Step 6: Final answer
   x = 1,171.15