Finding the Fourth Proportional to 1,039.20, 1,434.61 and 814.74

Step by Step Solution

1. Step 1: Write the proportion equation
   1,039.20 : 1,434.61 = 814.74 : x
2. Step 2: Convert to fraction form
   1,039.20/1,434.61 = 814.74/x
3. Step 3: Cross multiply
   1,039.20x = 1,434.61 × 814.74
4. Step 4: Simplify right side
   1,039.20x = 1,168,834.15
5. Step 5: Solve for x
   x = 1,168,834.15/1,039.20
6. Step 6: Final answer
   x = 1,124.74