Finding the Fourth Proportional to 1,398.32, 1,929.56 and 808.89

Step by Step Solution

1. Step 1: Write the proportion equation
   1,398.32 : 1,929.56 = 808.89 : x
2. Step 2: Convert to fraction form
   1,398.32/1,929.56 = 808.89/x
3. Step 3: Cross multiply
   1,398.32x = 1,929.56 × 808.89
4. Step 4: Simplify right side
   1,398.32x = 1,560,801.79
5. Step 5: Solve for x
   x = 1,560,801.79/1,398.32
6. Step 6: Final answer
   x = 1,116.20