Finding the Fourth Proportional to 1,317.98, 1,818.89 and 728.51

Step by Step Solution

1. Step 1: Write the proportion equation
   1,317.98 : 1,818.89 = 728.51 : x
2. Step 2: Convert to fraction form
   1,317.98/1,818.89 = 728.51/x
3. Step 3: Cross multiply
   1,317.98x = 1,818.89 × 728.51
4. Step 4: Simplify right side
   1,317.98x = 1,325,069.55
5. Step 5: Solve for x
   x = 1,325,069.55/1,317.98
6. Step 6: Final answer
   x = 1,005.38