Finding the Fourth Proportional to 1,308.45, 1,806.50 and 811.82

Step by Step Solution

1. Step 1: Write the proportion equation
   1,308.45 : 1,806.50 = 811.82 : x
2. Step 2: Convert to fraction form
   1,308.45/1,806.50 = 811.82/x
3. Step 3: Cross multiply
   1,308.45x = 1,806.50 × 811.82
4. Step 4: Simplify right side
   1,308.45x = 1,466,559.38
5. Step 5: Solve for x
   x = 1,466,559.38/1,308.45
6. Step 6: Final answer
   x = 1,120.83