Finding the Fourth Proportional to 1,405.93, 1,940.31 and 808.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,405.93 : 1,940.31 = 808.50 : x
2. Step 2: Convert to fraction form
   1,405.93/1,940.31 = 808.50/x
3. Step 3: Cross multiply
   1,405.93x = 1,940.31 × 808.50
4. Step 4: Simplify right side
   1,405.93x = 1,568,740.64
5. Step 5: Solve for x
   x = 1,568,740.64/1,405.93
6. Step 6: Final answer
   x = 1,115.80