Finding the Fourth Proportional to 1,397.85, 1,928.88 and 808.29

Step by Step Solution

1. Step 1: Write the proportion equation
   1,397.85 : 1,928.88 = 808.29 : x
2. Step 2: Convert to fraction form
   1,397.85/1,928.88 = 808.29/x
3. Step 3: Cross multiply
   1,397.85x = 1,928.88 × 808.29
4. Step 4: Simplify right side
   1,397.85x = 1,559,094.42
5. Step 5: Solve for x
   x = 1,559,094.42/1,397.85
6. Step 6: Final answer
   x = 1,115.35