Finding the Fourth Proportional to 1,318.17, 1,819.05 and 728.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,318.17 : 1,819.05 = 728.72 : x
2. Step 2: Convert to fraction form
   1,318.17/1,819.05 = 728.72/x
3. Step 3: Cross multiply
   1,318.17x = 1,819.05 × 728.72
4. Step 4: Simplify right side
   1,318.17x = 1,325,578.12
5. Step 5: Solve for x
   x = 1,325,578.12/1,318.17
6. Step 6: Final answer
   x = 1,005.62