Finding the Fourth Proportional to 1,309.38, 1,806.33 and 811.83

Step by Step Solution

1. Step 1: Write the proportion equation
   1,309.38 : 1,806.33 = 811.83 : x
2. Step 2: Convert to fraction form
   1,309.38/1,806.33 = 811.83/x
3. Step 3: Cross multiply
   1,309.38x = 1,806.33 × 811.83
4. Step 4: Simplify right side
   1,309.38x = 1,466,428.82
5. Step 5: Solve for x
   x = 1,466,428.82/1,309.38
6. Step 6: Final answer
   x = 1,119.95