Finding the Fourth Proportional to 1,405.16, 1,939.02 and 807.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,405.16 : 1,939.02 = 807.72 : x
2. Step 2: Convert to fraction form
   1,405.16/1,939.02 = 807.72/x
3. Step 3: Cross multiply
   1,405.16x = 1,939.02 × 807.72
4. Step 4: Simplify right side
   1,405.16x = 1,566,185.23
5. Step 5: Solve for x
   x = 1,566,185.23/1,405.16
6. Step 6: Final answer
   x = 1,114.60