Finding the Fourth Proportional to 1,438.71, 1,985.49 and 809.25

Step by Step Solution

1. Step 1: Write the proportion equation
   1,438.71 : 1,985.49 = 809.25 : x
2. Step 2: Convert to fraction form
   1,438.71/1,985.49 = 809.25/x
3. Step 3: Cross multiply
   1,438.71x = 1,985.49 × 809.25
4. Step 4: Simplify right side
   1,438.71x = 1,606,757.78
5. Step 5: Solve for x
   x = 1,606,757.78/1,438.71
6. Step 6: Final answer
   x = 1,116.80