Finding the Fourth Proportional to 1,155.76, 1,727.72 and 863.08

Step by Step Solution

1. Step 1: Write the proportion equation
   1,155.76 : 1,727.72 = 863.08 : x
2. Step 2: Convert to fraction form
   1,155.76/1,727.72 = 863.08/x
3. Step 3: Cross multiply
   1,155.76x = 1,727.72 × 863.08
4. Step 4: Simplify right side
   1,155.76x = 1,491,160.58
5. Step 5: Solve for x
   x = 1,491,160.58/1,155.76
6. Step 6: Final answer
   x = 1,290.20