Finding the Fourth Proportional to 2,629.55, 3,943.64 and 780.17

Step by Step Solution

1. Step 1: Write the proportion equation
   2,629.55 : 3,943.64 = 780.17 : x
2. Step 2: Convert to fraction form
   2,629.55/3,943.64 = 780.17/x
3. Step 3: Cross multiply
   2,629.55x = 3,943.64 × 780.17
4. Step 4: Simplify right side
   2,629.55x = 3,076,686.00
5. Step 5: Solve for x
   x = 3,076,686.00/2,629.55
6. Step 6: Final answer
   x = 1,170.05