Finding the Fourth Proportional to 2,659.38, 3,989.25 and 711.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,659.38 : 3,989.25 = 711.78 : x
2. Step 2: Convert to fraction form
   2,659.38/3,989.25 = 711.78/x
3. Step 3: Cross multiply
   2,659.38x = 3,989.25 × 711.78
4. Step 4: Simplify right side
   2,659.38x = 2,839,468.37
5. Step 5: Solve for x
   x = 2,839,468.37/2,659.38
6. Step 6: Final answer
   x = 1,067.72