Finding the Fourth Proportional to 1,405.83, 1,939.60 and 808.16

Step by Step Solution

1. Step 1: Write the proportion equation
   1,405.83 : 1,939.60 = 808.16 : x
2. Step 2: Convert to fraction form
   1,405.83/1,939.60 = 808.16/x
3. Step 3: Cross multiply
   1,405.83x = 1,939.60 × 808.16
4. Step 4: Simplify right side
   1,405.83x = 1,567,513.00
5. Step 5: Solve for x
   x = 1,567,513.00/1,405.83
6. Step 6: Final answer
   x = 1,115.01