Finding the Fourth Proportional to 1,439.52, 1,986.41 and 810

Step by Step Solution

1. Step 1: Write the proportion equation
   1,439.52 : 1,986.41 = 810 : x
2. Step 2: Convert to fraction form
   1,439.52/1,986.41 = 810/x
3. Step 3: Cross multiply
   1,439.52x = 1,986.41 × 810
4. Step 4: Simplify right side
   1,439.52x = 1,608,992.10
5. Step 5: Solve for x
   x = 1,608,992.10/1,439.52
6. Step 6: Final answer
   x = 1,117.73