Finding the Fourth Proportional to 1,405.63, 1,939.61 and 808.14

Step by Step Solution

1. Step 1: Write the proportion equation
   1,405.63 : 1,939.61 = 808.14 : x
2. Step 2: Convert to fraction form
   1,405.63/1,939.61 = 808.14/x
3. Step 3: Cross multiply
   1,405.63x = 1,939.61 × 808.14
4. Step 4: Simplify right side
   1,405.63x = 1,567,476.43
5. Step 5: Solve for x
   x = 1,567,476.43/1,405.63
6. Step 6: Final answer
   x = 1,115.14