Finding the Fourth Proportional to 1,289.97, 1,780.17 and 758.71

Step by Step Solution

1. Step 1: Write the proportion equation
   1,289.97 : 1,780.17 = 758.71 : x
2. Step 2: Convert to fraction form
   1,289.97/1,780.17 = 758.71/x
3. Step 3: Cross multiply
   1,289.97x = 1,780.17 × 758.71
4. Step 4: Simplify right side
   1,289.97x = 1,350,632.78
5. Step 5: Solve for x
   x = 1,350,632.78/1,289.97
6. Step 6: Final answer
   x = 1,047.03