Finding the Fourth Proportional to 1,290.86, 1,781.46 and 731.34

Step by Step Solution

1. Step 1: Write the proportion equation
   1,290.86 : 1,781.46 = 731.34 : x
2. Step 2: Convert to fraction form
   1,290.86/1,781.46 = 731.34/x
3. Step 3: Cross multiply
   1,290.86x = 1,781.46 × 731.34
4. Step 4: Simplify right side
   1,290.86x = 1,302,852.96
5. Step 5: Solve for x
   x = 1,302,852.96/1,290.86
6. Step 6: Final answer
   x = 1,009.29