Finding the Fourth Proportional to 2,629.57, 3,943.98 and 780.88

Step by Step Solution

1. Step 1: Write the proportion equation
   2,629.57 : 3,943.98 = 780.88 : x
2. Step 2: Convert to fraction form
   2,629.57/3,943.98 = 780.88/x
3. Step 3: Cross multiply
   2,629.57x = 3,943.98 × 780.88
4. Step 4: Simplify right side
   2,629.57x = 3,079,775.10
5. Step 5: Solve for x
   x = 3,079,775.10/2,629.57
6. Step 6: Final answer
   x = 1,171.21