Finding the Fourth Proportional to 2,728.52, 4,091.58 and 780.28

Step by Step Solution

1. Step 1: Write the proportion equation
   2,728.52 : 4,091.58 = 780.28 : x
2. Step 2: Convert to fraction form
   2,728.52/4,091.58 = 780.28/x
3. Step 3: Cross multiply
   2,728.52x = 4,091.58 × 780.28
4. Step 4: Simplify right side
   2,728.52x = 3,192,578.04
5. Step 5: Solve for x
   x = 3,192,578.04/2,728.52
6. Step 6: Final answer
   x = 1,170.08