Finding the Fourth Proportional to 1,308.71, 1,804.61 and 935.55

Step by Step Solution

1. Step 1: Write the proportion equation
   1,308.71 : 1,804.61 = 935.55 : x
2. Step 2: Convert to fraction form
   1,308.71/1,804.61 = 935.55/x
3. Step 3: Cross multiply
   1,308.71x = 1,804.61 × 935.55
4. Step 4: Simplify right side
   1,308.71x = 1,688,305.22
5. Step 5: Solve for x
   x = 1,688,305.22/1,308.71
6. Step 6: Final answer
   x = 1,290.05