Finding the Fourth Proportional to 1,405.52, 1,939.61 and 816.05

Step by Step Solution

1. Step 1: Write the proportion equation
   1,405.52 : 1,939.61 = 816.05 : x
2. Step 2: Convert to fraction form
   1,405.52/1,939.61 = 816.05/x
3. Step 3: Cross multiply
   1,405.52x = 1,939.61 × 816.05
4. Step 4: Simplify right side
   1,405.52x = 1,582,820.78
5. Step 5: Solve for x
   x = 1,582,820.78/1,405.52
6. Step 6: Final answer
   x = 1,126.15