Finding the Fourth Proportional to 1,309.94, 1,807.71 and 712.43

Step by Step Solution

1. Step 1: Write the proportion equation
   1,309.94 : 1,807.71 = 712.43 : x
2. Step 2: Convert to fraction form
   1,309.94/1,807.71 = 712.43/x
3. Step 3: Cross multiply
   1,309.94x = 1,807.71 × 712.43
4. Step 4: Simplify right side
   1,309.94x = 1,287,854.23
5. Step 5: Solve for x
   x = 1,287,854.23/1,309.94
6. Step 6: Final answer
   x = 983.14