Finding the Fourth Proportional to 1,290.82, 1,781.58 and 731.28

Step by Step Solution

1. Step 1: Write the proportion equation
   1,290.82 : 1,781.58 = 731.28 : x
2. Step 2: Convert to fraction form
   1,290.82/1,781.58 = 731.28/x
3. Step 3: Cross multiply
   1,290.82x = 1,781.58 × 731.28
4. Step 4: Simplify right side
   1,290.82x = 1,302,833.82
5. Step 5: Solve for x
   x = 1,302,833.82/1,290.82
6. Step 6: Final answer
   x = 1,009.31