Finding the Fourth Proportional to 1,399.02, 1,930.76 and 809.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,399.02 : 1,930.76 = 809.56 : x
2. Step 2: Convert to fraction form
   1,399.02/1,930.76 = 809.56/x
3. Step 3: Cross multiply
   1,399.02x = 1,930.76 × 809.56
4. Step 4: Simplify right side
   1,399.02x = 1,563,066.07
5. Step 5: Solve for x
   x = 1,563,066.07/1,399.02
6. Step 6: Final answer
   x = 1,117.26